Deathstroke Confirmed For Supergirl, Arrow, Flash, & Legends Crossover

In the latest teaser for The CW's four-show Invasion! crossover, eagle-eyed fans can get a glimpse of Deathstroke, the fan-favorite Arrow villain whose last appearance was about halfway through the show's third season.

Season 5 has returned to the roots of the show, with callbacks to the first season of the show and a darker, more action-driven aesthetic than season 4 had.

Speculation that Deathstroke would appear in the episode was kicked of back in September, when series star Stephen Amell has tweeted out an image of himself sitting on a park bench, looking very cross with the man on the other end -- Deathstroke.

Manu Bennett appeared throughout the show's first season as Slade Wilson before stepping into the role as season two's big bad in the Deathstroke costume. He would appear in one more episode, in season three, but has voiced his discontent with how his character was handled.

With the show's hundredth episode being what executive producer Marc Guggenheim called "a love letter to the show," could fans see their favorite villain once again in the form of either a current-day Deathstroke, or the season two version by the magic of time travel?

Deathstroke will be the villain in Ben Affleck's The Batman movie and possibly even show up in Justice League, which means it's not likely he'll be a major player in the big picture of Arrow again; Warner Bros. has shown a tendency to remove characters from most of their TV properties if those characters are going ot go on to play a bigger role in the movies.

Deadshot, Amanda Waller, and Katana -- members of the Suicide Squad cast -- all apeared in their Arrow form after Suicide Squad was already in production, and Affleck's Batman isn't in production yet.

Arrow, The Flash, and Supergirl will cross over with DC's Legends of Tomorrow next month in "Invasion!" a three-part crossover that starts in the final moments of an episode of Supergirl and then plays through the other series. Based on the 1988 comic book event miniseries Invasion! from Keith Giffen, Bill Mantlo, Todd McFarlane, Bart Sears, and more, EW confirms that it will closely track the plot of that storyline: aliens will be assembled by The Dominators and descend on Earth to bring an end to the "threat" of Earth's burgeoning metahuman community.

Along the way, of course, the middle chapter of the epic crossover will also be the hundredth episode of Arrow. It seems as though that episode will be a bit of an act break, in which Arrow gets to take stock of its own history in the context of the larger story.

"I do get to punch an alien, but not in the hundredth episode of Arrow," series star Stephen Amell told ComicBook.com at the Arrow 100th episode party two weeks ago. "The hundredth episode of Arrow begins in a very appropriate way: it begins with Oliver running."

That's a recurring motif; this was the first season where Oliver hadn't run into the season, and so leaving it for the crossover was one of a number of ways the hundredth episode was able to nod at the show's history.

"We utilize the crossover to ostensibly allow us to do whatever we want for the one hundredth," Amell said. "So it's almost like the writers have a blank canvas."

Supergirl airs Mondays at 8 p.m. ET/PT; The Flash on Tuesdays at the same time; Arrow on Wednesdays and DC's Legends of Tomorrow on Thursdays. All four series air on The CW. The "Invasion!" crossover will air beginning November 28.