'Arrow's 150th Episode Brings Back Fan Favorites & Adds New Layers to Maya's Mystery

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The CW

The OG series of The CW's DC Comics lineup celebrated a major milestone on Monday.

Arrow hit its 150th episode on Monday and marked the occasion by bringing back some familiar faces and introducing more intrigue surrounding a mysterious new character.

The flagship series of The CW's DC Comics 'verse celebrated its latest milestone with a documentary episode entitled "The Emerald Archer" -- the same as the title of the doc being produced about the unmasked, newly deputized Green Arrow, Oliver Queen (Stephen Amell), which explores "The Hood and the Rise of Vigilantism."

Narrated by Kelsey Grammer, the documentary features found footage of Star City's vigilantes in action, as well as interviews with residents past and present that the filmmaker (Jessica Heafey) has been compiling throughout the years. This is a treat for fans, who get some blasts from the past in bites from season one fan-favorite Cindy "Sin" Simone (Bex Taylor-Klaus) and former Team Arrow member Rory "Ragman" Regan (Joe Dinicol) -- as well as Oliver's sister, Thea Queen (Willa Holland), now-Legend Sara Lance (Caity Lotz) and her late father, Quentin Lance (Paul Blackthorne). There's even a quick appearance from Barry Allen (Grant Gustin), who pokes fun at his heroic pal while stumbling over his own secret identity as The Flash.

However, the documentary -- which also sees the return of Oliver's son, William (Jack Moore), from boarding school and the mayor deputizing all of Team Arrow after they unite to stop a villain who is dead-set on "collecting" vigilantes -- serves another purpose, as the final moments flash to the future Star City timeline, where Maya (Kat McNamara), the tough-as-nails street fighter known as Blackstar, is watching the film. Her friend, Connor (possibly Connor Hawke, aka John Diggle Jr.?), asks after the film, noting that he thought all copies of the documentary had been destroyed after it was banned. "Not this one," she answers mysteriously.

The two then travel to the old Team Arrow bunker, now desolate and overgrown. Arrow fans know that Maya was the last one to have contact with Felicity Smoak (Emily Bett Rickards) before her disappearance at some point in the future, but she doesn't seem to be too impressed with the work that the tech genius and her heroic friends did with their time in the underground lair.

“Vigilantes were the death of Star City," Maya tells Connor, with a grimace, "and they got exactly what they deserved.”

ET spoke with McNamara last fall, who teased her mysterious character as "a fighter. She's someone not to be messed with, I'll put it that way."

"But it's been a real joy," the actress said of transitioning from the Shadowhunters family to Team Arrow. "That's such a family and I was welcomed with open arms and it's such an exciting thing." 

See more in the video below. Arrow airs Mondays at 8 p.m. ET/PT on The CW.