Major spoilers below for the entirety of The Flight Attendant Season 1, now make sure your seat is in an upright position before reading on.
With all eight of its episodes dropping in than a month, HBO Max's acclaimed thriller The Flight Attendant gave viewers a winter send-off with the TV equivalent of a summer beach read. Based on the actual book from author Chris Bohjalian, The Flight Attendant delivered plenty of drunken turbulence for Kaley Cuoco's Cassie Bowden and a variety of other characters ahead of the Season 1 finale. But it all came to an end (for now) with the episode "Arrivals and Departures," which tied up the storyline's loose threads in ways that practically begged for a second season to be ordered.
In fact, The Flight Attendant's finale would arguably amount to a pretty frustrating hour of television had HBO Max not made just such a Season 2 order the day after the finale was released. But let's go through all the major beats below, from the definitive answer to who killed Michiel Huisman's Alex Sokolov, to how Cassie fared in the end, to a twist that came completely out of left field.
Alex Sokolov's Murderer Was Definitely Felix/Buckley
As it was more or less confirmed in Episode 7, Cassie's drunk lover Buckley (Colin Woodell) was actually an assassin named Felix who was actually responsible for killing Alex Sokolov. Viewers learned that Felix was not only on the same flight where Cassie and Alex met, but also that he posed as room service on the night of the murder and gave the duo their strong drinks. Felix thought he was gaining access to Alex's funds before slitting his throat, but soon realized that Alex's final words had been a ruse.
After that night, Felix followed Cassie all over the world, and eventually accosted her in Rome, though luckily after she'd secured a handgun from her sometimes-lover Enrico. (Technically from his dead grandfather.) Felix attacked both Miranda and Enrico before getting his hands on Cassie, who put up quite a fight. She was able to use the gun on him as well, though it was her co-worker Shane (Griffin Matthews) who burst through the door just in time to take Felix down. Felix did survive the ordeal, however, so don't be surprised if he shows up in Season 2 in some way, perhaps in Cassie's new mind palace.
The Flight Attendant's Ending Differed From The Novel
On the whole, The Flight Attendant's showrunner Steve Yockey introduced quite a few alterations from the novel as Season 1 went along, allowing it to reach its specific live-action conclusions. But perhaps the biggest change was the identity of Alex's killer, which was not Felix but Miranda. Had Miranda turned out to be the guilty party in the HBO Max series, that would have potentially hindered Michelle Gomez from being able to tonally own the role so well once her character factored into the story more in later episodes. Here's how Yockey explained the decision to change things up to TVLine:
It’s faithful to the book, though he is not the killer in the book; he is just a person that is hunting Cassie. In the book, Miranda killed Alex, so we made changes that we thought would not so much isolate us from people who had read the book, but give us that Game of Thrones experience where people who’ve read the book are like, 'Oh yeah, just wait until this happens.' We thought it’d be fun for people who have read the book if we are also surprising them as well.
Beyond that major reveal, the Flight Attendant novel also delivered a late-game reveal that Cassie was pregnant with Alex's baby, which tied in with the character's motherhood-esque longing on the page. Steve Yockey explained to Glamour that because the TV show's focus on Cassie was more about her journey of self-discovery, they decided to excise the pregnancy twist.
Cassie Got Sober And Is Mentally At Peace (For Now)
Cassie realized late in the season that her beer-swilling youth with her father, along with his drunk-driving death, were the key contributors to not only her own alcoholism, but also her wavering relationship with T.R. Knight's Davey and others. After having a mini-heart-to-heart conversation with Enrico's grandmother, Cassie drew a line in the metaphorical sand by emptying her purse of all her tiny vodka bottles – it was comparable to a clown car, truly. As revealed in her apologetic meet-up with Zosia Mamet's Annie, Cassie had her first AA chip and had already attended two meetings, though she was aware of how difficult the road to recovery would be.
As well, once Alex's murder was solved, Cassie was able to say goodbye to him within her mind palace, though she made sure not to remember him as a bloodied victim, but rather as the dashing businessman she fell for before he died. At the very end of the episode, Cassie is able to close off the rooms within that particular mind palace, but that concept might not be gone forever. As Steve Yockey put it to TVLine, a different-looking version of the character's mental haven will very likely be utilized for Season 2, though it's not yet clear how that would be worked out. Just know that it'll likely be completely free of Huisman's Alex.
Shane The Flight Attendant Is Actually Shane The CIA Agent
One of the most baffling moments in the entirety of The Flight Attendant Season 1 came when Griffin Matthews' Shane burst through the door of Cassie's hotel room and shot Felix down. Soon after, Shane revealed that beyond all his skills as a sassy flight attendant, he's also secretly a CIA agent who was tasked with keeping tabs on Rosie Perez's Megan and her own illegal activities.
Shane's reveal wasn't meant to only be a strange left turn, however. His CIA ties are a key factor in how The Flight Attendant will extend its story into Season 2 and beyond, as Shane told Cassie that his bosses were somewhat impressed by her sleuthing skills, though he almost definitely didn't disclose how many gallons of vodka she went through during her investigation. In any case, the CIA is looking to turn Cassie into an asset, which will likely lead to her getting invested in further murders and other serious crimes for a second season.
Megan Is On The Run
With a storyline that arguably never felt quite as fleshed out as it could have been, Rosie Perez's Megan made efforts to set things straight with both Cassie and her family in the finale. She and Cassie reaffirmed their friendship, though it might be a while before they hang out again, considering Megan chose to become a fugitive rather than turn herself in. But before she headed out on a train, Megan put a call in to her son where she tearfully expressed her love for him and told him where the dad could find all of the data and information that would clear his name with authorities. It's presumed she'll be back in Season 2, but it's hard to say for sure, since we're not even sure where she's going.
Miranda Definitely Survived
Even though it seemingly looked like Felix may have killed Miranda in the finale, with her laid out in Cassie's hotel bathtub, audiences had already learned just how resourceful the quasi-antagonist was. As such, it was no big shocker to discover that she'd somehow made her escape in the midst of Cassie and Felix's confrontation. Without any explanations, it's unclear exactly what happened, but Miranda did make a brief, unseen return before it was all over. As Cassie had her reunion lunch with Annie, she realized that Alex's scribble-filled book had been left in her jacket, with Miranda having ripped out the pages with Alex's bank info. So Miranda is presumably off spending other people's money somewhere, but she'll likely return in Season 2 in some way.
How Other Flight Attendant Side Characters Fared
Cassie and her brother Davey reconnected in the end after he made the trip to check up on her, and it seems like their relationship will continue growing when Season 2 arrives.
Though he was stabbed by Felix in the hotel room (following that unintentional Big Bang Theory reference), Enrico was shown to still be alive as he was wheeled out by emergency workers. It's not likely he'll play a major role in Season 2, especially when his grandmother finds out what happened.
Annie's boyfriend Max survived being trampled by a car, which definitely helped Annie and Cassie's friendship to stay intact, since it appeared Annie was going to excise her friend completely had Max's health situation gone the other way.