Oliver Queen has lost a lot of people in the years that Arrow has been on the air, and not all of them have had access to a magical pool of resurrection water. One of the most tragic deaths to date has been Moira Queen, who was murdered in front of both of her children in Season 2. Now, actress Susanna Thompson has signed on to return to Arrow as Moira for the 100th episode of Arrow, which means one thing: Oliver is in for a rough emotional journey in his milestone episode.
Arrow fans will remember well the scene of Moira volunteering herself as Slade WIlson's victim when he was forcing Oliver to choose between his mother and his sister. Slade acknowledged her for her bravery...then ran her through with a sword. It started the grand tradition of Queens being stabbed with ginormous blades, and it was a magnificent performance by Susanna Thompson.
Unfortunately, Thompson has been absent from the series since Season 2, not even appearing via flashback. Little is currently known about how and why Moira will be back on Arrow, according to EW. Still, the news that she'll be reprising Moira for the 100th episode is definite cause for celebration for fans who have been missing the Queen matriarch for the past couple of years.
It actually makes a lot of sense that Susanna Thompson is returning for the 100th episode. The hour is set to feature other characters from Oliver's past who have died. Jamey Sheridan will be in the thick of things as Robert Queen, and Katie Cassidy will turn up again as Laurel Lance. Some version of Deathstroke will appear in Episode 100 as well. For Oliver's sake, as well as all of ours, I hope he doesn't have to watch Deathstroke murder his mom again.
Of course, we don't yet know the circumstances that will bring these deceased characters onto Arrow. Executive producer Marc Guggenheim already revealed that Robert's return won't be as part of flashbacks or as a result of the Flashpoint story from The Flash, and it's safe to assume that the circumstances that bring Moira back to Arrow will be the same as what bring back Robert.
Given that Episode 100 will be part of The CW's massive DC crossover, my guess is that the Moira who turns up will be the Moira from another Earth. The precedent was set when Barry jumped to Earth-2 last year on The Flash, so Oliver's dead loved ones in Episode 100 could well be folks from Earth-3 or -4 or -5. Seeing them again and then having to say goodbye again could be one of the most difficult challenges that Oliver has ever had to face (unless they're total douches). I won't be shocked if the 101st episode features a decidedly gloomy Green Arrow.