A television and pop culture fixture since its debut in 1963, Doctor Who has seen a lot of cast departures in its long and involved history. It’s natural, with Companions and Doctors all having various reasons for deciding to step out of the TARDIS and into the history books. With a huge span between 1989 and 2005 during which the show wasn’t running (save for a TV movie in 1996), there’s a lot of history to cover if you’re a fan of the series that helped make David Tennant and Matt Smith both household names.
For the sake of time, brevity, and the fact that the modern age is what the focus is mostly on with the Doctor Who franchise these days, we’ll be looking at those various departures as they took place throughout the run of Doctor Who that started with 2005’s revival. We’ll going through the different major characters that came and went, their vital characteristics, and ultimately why they left and how they were written off.
All of time and space are waiting, and the starting point in this journey is pretty obvious, as a rather big departure at the end of Season 1 marked the first big shift in Doctor Who history.
Christopher Eccleston (The Ninth Doctor)
Seasons Active: Season 1
The first of the modern Doctor Who Doctors, Christopher Eccleston’s Ninth Doctor was a man haunted by his past. The last survivor of the Time War between the Time Lords and the Dalek race, this Doctor did the unthinkable in order to end this horrid conflict. Dour and remorseful, he had a lot to learn about forgiveness and lightening up, but before he departed, he eventually did.
Why The Actor Left: In the early days of Doctor Who, Christopher Eccleston was the man who would come to represent the show’s new face for a modern age. Yet, backstage politics weighed him down, and soured his impression of the experience of making the show. Eccleston decided to leave before Season 1 even aired and The BBC, in apparent breach of contract, announced as the show was just starting to air that they had cast David Tennant as the next Doctor.
How The Character Was Written Off: After kissing Rose Tyler to drain a lethal dose of TARDIS radiation from her body, The Ninth Doctor restored the energy to the heart of the TARDIS. Of course, this came at a price, as the Time Lord would have to regenerate for the first time in modern series history. Using his special way of cheating death, The Doctor exploded in cosmic energy, and eventually turned into The Tenth Doctor, ready to take that trip to Barcelona he promised dear Rose.
Billie Piper (Rose Tyler)
Seasons Active: Seasons 1 & 2
A young woman in search of adventure, Rose Tyler met The Doctor by chance. After being saved from the Auton invasion, and being left unemployed in the process, Rose eventually became the companion to The Doctor. Growing from a naïve citizen of Earth to a take-charge sidekick who could hold her own, Rose finally made an impression on The Doctor and they became inseparable. Until, one day, fate tore them apart.
Why The Actor Left: Being one of the stars on a show like Doctor Who is pretty exhausting, particularly given everyone is prone to speculating about what’s going to happen next. As such, Billie Piper found herself overwhelmed by how much the series had taken priority in her life. So by time Season 2 came around, Piper decided to leave the show; just one season in with the new Doctor she’d forever be associated with, David Tennant. Though eventually, Billie Piper did return for a guest spot in Season 4, completing her story in the television series for good.
How The Character Was Written Off: During the Battle of Canary Wharf, where The Daleks and The Cybermen waged all-out war for control of the Earth, The Doctor and Rose closed the dimensional rift that allowed both warring races to cross over into our realm in the first place. Rose was almost sucked into the dimensional void that both aliens were being sent back to, but thanks to an alternate reality version of her father, Pete, Rose was whisked away to a parallel reality that she and The Doctor had visited earlier. Sealed off from our world for good, she was never to see The Doctor again. But a huge event let her return to our world, and when she went back to her home in the alternate universe, she was sent back with a humanoid clone of The Tenth Doctor, who she could live happily ever after with. Though Rose would finally appear as a vision to The War Doctor, in an effort to dissuade him from destroying the Time Lords and the Daleks in "The Day of The Doctor."
Freema Agyeman (Martha Jones)
Seasons Active: Season 3
Before she met The Doctor, Martha Jones was a medical student who had her future mapped out, complete with her loving fiancé and eccentric family. Those are the sorts of things that get thrown out the window when The Doctor came to call, and becoming his companion did take her away from everyone she knew and loved. Though she didn’t mind, as she had a huge crush on The Doctor throughout their time together as Time Lord and Companion.
Why The Actor Left: With The Tenth Doctor and Rose still enduring as one of the most iconic pairs in Doctor Who history, fan reaction wasn’t as abundant when it came to Martha’s turn to shine. Therefore, she was written off after the end of Season 3, with Martha reappearing a couple times toward the end of David Tennant’s run, as well as becoming a character in the second season of the spin-off series Torchwood.
How The Character Was Written Off: After living through an alternate year of human history as a revolutionary fighting The Master, Martha Jones was done traveling through time and space. Accepting The Doctor’s rejection of her romantic advances,and finding herself more confident than ever, she left the TARDIS and struck it out on her own. Martha would later work for Torchwood along with Captain Jack Harkness, and would eventually marry Mickey Smith, Rose Tyler’s ex-boyfriend.
Catherine Tate (Donna Noble)
Seasons Active: Season 4
Before Martha Jones had come into his life, The Tenth Doctor palled around with someone he’d soon meet again in the wake of Martha’s departure. Donna Noble, the “runaway bride," was accidentally intercepted by the TARDIS shortly after The Doctor said goodbye to Rose Tyler for the (supposedly) final time. After fighting the Racnoss Empress on what was supposed to be her wedding day, Donna would develop a nose for unusual goings on,in hopes that she’d meet up with her friend The Doctor yet again.
Why The Actor Left: Donna Noble was always intended to be a one-season companion, per the plans made by then show-unner Russell T. Davies. This moment was shocking, but as most big fissures in Doctor Who history tend to be, it was also planned for.
How The Character Was Written Off: One of the MOST important rules as a Companion is and always will be: Don’t touch anything that contains powers beyond human comprehension;,unless you have permission. Donna Noble, for one brief moment in time, was a human/Time Lord metacrisis, a human being with the powers of perception of a Time Lord. That sort of thing fries a human brain out really quickly, and unfortunately The Doctor had to do something he never wished he’d had to do, which was to wipe Donna’s memories of traveling with him, in order to save her mind. She reappeared briefly in David Tennant’s two-part finale, “The End of Time," but that was the end of Donna’s story, as she married and lived happily ever after, with a fortune won by The Doctor.
John Barrowman (Captain Jack Harkness)
Seasons Active: Season 1 & Season 3
Dashing, debonair, and willing to bunk down with anyone with a postcode, Captain Jack Harkness was one of Doctor Who’s most iconic recurring characters. Always willing to flirt with Doctor and Companion alike, Jack traveled through time via a time vortex manipulator, and was made pretty much immortal due to Rose Tyler resurrecting him with the power of the TARDIS. This, by some with shaky marriages and/or evil designs against the Earth, was considered a very bad idea.
Why The Actor Left: With Captain Jack Harkness taking a major role in the Doctor Who spin-off Torchwood, John Barrowman was able to cross over into Doctor Who a couple of times, but was never a terribly huge fixture on the show. When Russell T. Davies left his duties as showrunner, Captain Harkness just wasn’t brought back into the Doctor Who fold. That didn’t stop him from building a fanbase though, and eventually, it came time for Captain Jack to run off into Torchwood history, with that series eventually ending in its televised form in 2011.
How The Character Was Written Off: Much like Martha Jones, Captain Jack Harkness left after he, Martha, and The Doctor unwound a whole year of the planet being under the control of The Master. Doing his usual duties as an agent of time protection and seduction, he went off on more Torchwood adventures, and eventually became The Face of Boe – a mysterious head in a gigantic jar, who had previously assisted The Doctor in his Ninth incarnation, as well as earlier in Season 3.
David Tennant (The Tenth Doctor)
Seasons Active: Seasons 2 – 4
Quite possibly the most popular Doctor of the modern era of Doctor Who, The Tenth Doctor was a burst of energy that lead to Matt Smith’s Eleventh Doctor, but also carried over some of the dour energy that Christopher Eccleston’s Ninth Doctor exhibited. At some points carefree, and at others remorseful, this Doctor was shattered when Rose Tyler left, and took quite a bit of time getting over her departure.
Why The Actor Left: Another party who decided to leave before outstaying their welcome, David Tennant announced his departure from Doctor Who during, out of all places, an awards acceptance speech. After a set of specials rounding out his tenure, Tennant yielded to Matt Smith, and then-showrunner Russell T. Davies ceded his position to writer Steven Moffat.
How The Character Was Written Off: After defeating The Master yet again, The Doctor had to save temporary Companion/grandfather of Donna Noble, Wilfred Mott, by sacrificing a Regeneration. Absorbing a fatal dose of radiation, and freeing Wilf from a glass booth he was trapped in, The Tenth Doctor withheld his Regeneration just long enough to take a farewell tour to see his past companions and other friends. With the final line, “I don’t want to go," Ten exploded into his metamorphosis, wrecking his TARDIS and causing a crash landing.
Karen Gillan (Amy Pond)
Seasons Active: Seasons 5 – 7.1
When The Eleventh Doctor crash-landed onto Earth, Amy Pond was but a young girl. By the time The Doctor returned to check up on her, she was a young woman who had been treated as if she were crazy, talking about a raggedy man with a big blue box. Soon, she learned she wasn’t losing her mind, and would become one of the most iconic companions ever, alongside her eventual husband Rory, and her daughter, Professor River Song.
Why The Actor Left: In choosing what she felt was best for her character, Karen Gillan decided that it was time to leave Amy Pond behind. So in the first half of Season 7, both Amy and her husband Rory were written off. While Gillan would go on to direct her own films, as well as becoming an important part of the Marvel Cinematic Universe, she did make one final appearance post-write off, to say goodbye to Matt Smith’s Eleventh Doctor.
How The Character Was Written Off: After Rory was taken by a Weeping Angel, and sent back into the past at the end of The Angels Take Manhattan, Amy decided to be taken by the same Angel in order to be with Rory. With a tearful goodbye to The Doctor and River Song, Amy was whisked away. She later appeared as a hallucination to The Eleventh Doctor as he regenerated, though she died at the age of 87 after going to live with Rory in the past.
Arthur Darvill (Rory Williams)
Seasons Active: Seasons 5 – 7.1
Rory Williams was, and always had been, in love with Amy Pond. His love for her was stronger than any other romantic pairing outside of The Doctor and his beloved wife, River, and it showed in many forms of heroism that Rory would exhibit over his time as a Companion. If there was one phrase that summed up Rory’s devotion to Amy, it was probably this: “Together, or not at all.”
Why The Actor Left: Amy and Rory were a package deal. Once Karen Gillan decided to leave the show, it was pretty much a given that Arthur Darvill would be written out alongside her. Though Darvill would later meet up with another former Doctor, as he would become a star in future showrunner Chris Chibnall’s popular drama Broadchurch, which just happened to star one David Tennant.
How The Character Was Written Off: After one final adventure into 1930’s New York, alongside The Doctor and his daughter, River Song, Rory was taken by surprise by a Weeping Angel. Sent back into time, Rory lived out his days alongside Amy, and passed at the age of 82.
Matt Smith (The Eleventh Doctor)
Seasons Active: Seasons 5 – 7
After regenerating due to the events of “The End of Time," The Eleventh Doctor made a fresh start in the Doctor Who canon. Matt Smith’s interpretation of the legendary Time Lord was a big ball of fun, with some relatively sad moments sprinkled in here and there. For the most part, Eleven was ready to run into battle when he had to, and he’d usually do so smiling and with perfect hair.
Why The Actor Left: Considering The Doctor was originally intended to be written as an older incarnation when then-showrunner Steven Moffat took over, Matt Smith’s casting was a bit of a surprise for some. But it was a welcome one, as he eventually racked up three seasons of merriment, after which he decided it was time to hang up his bow tie. Moffat originally was going to depart alongside Smith, which may have played a part in the actor’s decision, but ultimately Matt Smith felt his time had come.
How The Character Was Written Off: After aging into an old Time Lord on his supposedly final bow, with a Dalek armada facing him down on Trenzalore, it looked like The Doctor was finished. Thanks to Clara earning him a new regeneration cycle, The Eleventh Doctor used huge bursts of his newfound energy to take out his enemies in spectacular fashion. This gambit came with a cost: Eleven had to regenerate, turning him into The Twelfth Doctor, and scaring the living hell out of Clara, his current companion. Though he would eventually appear one last time, calling Clara from the past to explain how he'd shifted into his latest form, in the Season 8 premiere "Deep Breath."
Alex Kingston (Professor River Song)
Seasons Active: Seasons 4 – 7, Season 9
Starting as an enigmatic love interest, Professor River Song died the first time she met The Doctor. As any time traveler will tell you though, that doesn’t mean you have to stop dating. As their romance would progress through time, their personal timelines never matched up. This was a fact that allowed twists such as Companion Amy Pond being River’s mother to be deployed so skillfully. Bold, smart, and daring, she went from the woman who would kill The Doctor to the person who was his greatest love.
Why The Actor Left: Alex Kingston’s Professor River Song was always written with a limited lifespan on Doctor Who. Eventually, with her appearance in “The Many Husbands of River Song," her arc was fulfilled and her loop was closed. However, knowing the nature of the show, Kingston has stated that if there was an opportunity, she’d love to come back and have some fun with Jodie Whitaker’s Thirteenth Doctor.
How The Character Was Written Off: The first time The Doctor ever laid eyes on her, in his younger David Tennant form, was on River’s last day of life. It was written that the last time River would ever see the Doctor was when she sacrificed herself to save the patrons trapped in the cloud of The Library. But the last time we see her on the series is right before that event, when the Twelfth Doctor takes her on their fateful date at the Singing Towers of Darillium, just before she travels back in time to meet her husband for the first-last time.
Jenna Coleman (Clara Oswald)
Seasons Active: Season 7 – 9
Born to save The Doctor, Clara Oswald made her first contact with the iconic Gallifreyan in “Asylum Of The Daleks”, as she was trapped inside of a Dalek consciousness. As it turned out, Clara would enter the timestream of The Doctor’s lifetime to save him at crucial points of each of his incarnation’s lives. She not only traveled with The Eleventh Doctor, but she also ran with his Twelfth iteration as well, serving as the longest-running Companion in the modern era.
Why The Actor Left: Jenna Coleman’s departure from the Doctor Who cast came down to a simple fact: Her contract ran up, and it was mutually decided that she would move on to other things. With an extra year built in for Coleman to wrap the story of Clara properly, the future star of the hit period drama Victoria brought Ms. Oswald’s story to a prompt close.
How The Character Was Written Off: Clara was supposed to die after taking on a death sentence in the episode “Fear The Raven," but thanks to The Twelfth Doctor attempting to cheat her death, she was removed from that moment in time and thus lived against the flow of time. Eventually, things had to be set right, and Clara was sort of reassigned as a Companion to Maisie Williams’ rogue Time Lord, Ashildr. With his memory wiped of Clara, The Doctor went on with his adventures, while Clara travelled the universe with Ashildr. Her last episode was "Twice Upon A Time."
Pearl Mackie (Bill Potts)
Seasons Active: Season 10
A university student who came across The Twelfth Doctor during his time as a professor on Earth, Bill Potts soon learned of the universe’s much weirder and adventurous side as his eventual companion. Serving alongside Nardole, Twelve’s other companion during his final season, Bill would challenge The Doctor in ways others would not dare. She would also suffer one of the worst twists of fate to befall any Companion in the modern era.
Why The Actor Left: As Steven Moffat was leaving as showrunner, there was a change to come in the world of Doctor Who. With his replacement, current showrunner Chris Chibnall, looking to shake things up with the series, he not only hired Jodie Whitaker as the new Doctor, but he also wiped the slate clean in terms of Companions. So alas, Pearl Mackie was a companion no more.
How The Character Was Written Off: Temporarily turned into a Cyberman, Bill Potts rejected the typical programming of one of the most classic adversaries in the Doctor Who canon. She helped The Doctor defeat the cadre of Cybermen in the episode “The Doctor Falls," and ultimately found herself given a choice: to be restored as a Human, or to be transformed into a being who could travel the universe, much like her girlfriend Heather. Choosing the latter, Bill left The Doctor, and began her grand adventure with a reappearance in “Twice Upon A Time” serving as her last Doctor Who appearance.
Matt Lucas (Nardole)
Seasons Active: Seasons 9 & 10
Originally a one-off associate to Professor River Song in “The Husbands of River Song” Christmas special, Matt Lucas’ Nardole eventually became friends with The Twelfth Doctor, and tagged along for the entirety of Season 10, as well as its preceding Christmas Special “The Return of Doctor Mysterio." Tasked with looking after The Doctor after River’s death, Nardole served as a grounding presence with a comedic wit, who would eventually serve along with his co-Companion, Bill Potts.
Why The Actor Left: Much like Amy and Rory, Nardole and Bill were kind of a package deal when it came to their fate in the Doctor Who cast. Since Bill Potts was being scrapped in favor of the new Companion Fam that Thirteen is swanning about with, Matt Lucas was also sent off at the same time Pearl Mackie was written out of the show.
How The Character Was Written Off: As The Doctor prepared to destroy the Cybermen in an attempt to save a ton of humans from being converted, he ordered Nardole to evacuate everyone that he could in the process. Eventually, on another level of the space station base where the Cybermen planned and converted their army, the faithful companion awaited the potential invasion in order to finish the conversion, ready for battle. Thankfully, this was never to be, and Nardole’s memory appeared alongside Clara and Bill’s in “Twice Upon A Time," in order to send The Doctor off in sentimental fashion.
Peter Capaldi (The Twelfth Doctor)
Seasons Active: Seasons 8 – 10
It was predicted The Doctor would eventually become an older man again, and sure enough Peter Capaldi’s Twelfth Doctor brought to life a man that Steven Moffat had previously described before he took on the reins as Doctor Who's showrunner. While The Doctor was now a more aged and seasoned version of himself, he wasn’t any less eccentric or battle ready, as Capaldi’s tenure would have some fun flourishes, such as The Doctor’s ability to play the electric guitar.
Why The Actor Left: Between representing the brand of Doctor Who, and his own feelings about not wanting to overstay his welcome, Peter Capaldi left the role of the Twelfth Doctor at the end of Season 10. With his departure, showrunner Steven Moffat also decided it was time to hang it up, and the pair ushered out an era of Doctor Who history that finally built a bridge between the classic era and the modern age of this legendary canon.
How The Character Was Written Off: Defying his Regeneration yet again, The Twelfth Doctor refused to change into his next form. But an adventure with a similiarly defiant First Doctor, and the Christmas Armistice of 1914, changed The Doctor’s mind and allowed him to change into his latest form: the female Thirteenth Doctor.
Throughout the history of Doctor Who, change has always been the constant. Who knows what departures we'll see next, in this newly revitalized era of Jodie Whitaker's Thirteenth Doctor and the many Companions she has banded together in her journeys across time and space. At the very least, we won't know until Doctor Who returns at some point in 2020, with the streaming rights to Seasons 1 - 11 going to HBO Max earlier in that same year.