James Gunn's The Suicide Squad starts production this September and is scheduled for release on Aug. 6, 2021. It's unclear whether the Guardians of the Galaxy director's film is a sequel to the much-criticized 2016 Suicide Squad movie, a reboot or something in-between. Gunn currently says "it is what it is."

What is clear is that the film will focus primarily on new characters, though a few stars from the first film will return. Which DC antiheroes and villains have been confirmed to appear, and which ones have been rumored?

RETURNING CHARACTERS

harley suicide squad

Three cast members from the first Suicide Squad are confirmed to be returning. Margot Robbie's Harley Quinn was the break-out fan-favorite character from the previous film and is set to return in some capacity. Between this and the Birds of Prey film, she's quickly becoming one of the star attractions of the DC Extended Universe. Viola Davis will also be returning as team organizer Amanda Waller, and Jai Courtney's Captain Boomerang is also confirmed to be in the movie.

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Rick Flag leading the Suicide Squad in the field

Joel Kinnaman's Rick Flag might also return. No official announcements have been made, but many are taking the actor's Instagram post about "squad prep" as confirmation. Beyond that, it's safe to assume the rest of the first film's characters won't be returning. Initial rumors that Deadshot, played by Will Smith in the first movie, would be recast have since been debunked.

CONFIRMED: POLKA-DOT MAN & RATCATCHER

Two new squad members have been officially cast. David Dastmalchian is playing Polka-Dot Man. One of the lesser-known villains from Batman's campy Silver Age comics, Polka-Dot Man is able to use the spots on his suit as weapons. Making audiences take one of the most ridiculous characters possible seriously seems like a fitting challenge for the director who made audiences fall in love with a talking raccoon and a tree alien.

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Suicide Squad 2: Who's Who in James Gunn's DC Reboot

Another character from the more obscure end of the Batman rogues' gallery, Ratcatcher is also confirmed to be in The Suicide Squad. This character's most distinctive power is the ability to communicate with and control sewer rats. The movie version will differ from the comics version in at least one major way: While the comics' Ratcatcher is male, the movie adaptation will be played by Daniela Melchior.

IDRIS ELBA AS... SOMEONE

Idris Elba Batman
TORONTO, ON - SEPTEMBER 10: Actor Idris Elba speaks to the media at the premiere of "The Mountain Between Us" during the 2017 Toronto International Film Festival at Roy Thomson Hall on September 10, 2017 in Toronto, Canada. (Photo by J. Countess/WireImage)

Idris Elba, People's Sexist Man Alive and the internet's favorite actor to fancast in everything, is going to play a major role in The Suicide Squad. What his role is, we don't know yet. Originally it was reported he was replacing Will Smith as Deadshot, but those rumors have been shot down. Elba will most likely play a new character to be introduced in this film.

Geeks Worldwide claims that Elba's role is between the evil athlete Sportsmaster, most likely the Victor Gover incarnation if we're looking at past Suicide Squad line-ups, and Deathstroke. The latter wouldn't exactly be a new character in the DCEU, having previously been played by Joe Manganiello in Justice League's post-credits scene, but it would certainly be a distinctive reimagining of the Teen Titans' classic nemesis. Forbes has pointed in a different direction, claiming Elba is likely playing the martial artist Bronze Tiger (previously played by Michael Jai White on The CW's Arrow).

JOHN CENA AS PEACEMAKER?

Originally, James Gunn wanted to cast Dave Bautista, the Guardians actor who stood up most vocally in the director's defense following his temporary firing from Guardians 3, for a role in The Suicide Squad. Bautista's schedule is packed, however, so now this role is set to go to another wrestler-turned-actor, John Cena.

RELATED: The Suicide Squad: Idris Elba Might Be Playing THIS Character

When covering on the casting talks, Variety reporter Justin Kroll couldn't confirm what this role was specifically, but believed it was for the part of Peacemaker. A Charlton Comics character later acquired by DC, Peacemaker is a "pacifist" haunted by mental illness and the memories of his Nazi father, driving him to violence in the name of peace. He was the inspiration for The Comedian in Watchmen.

NOT MICHAEL ROOKER AS KING SHARK

The humanoid shark King Shark has been rumored as part of The Suicide Squad's team since March. Given that other characters he was rumored alongside have since been confirmed (Ratcatcher and Polka-Dot Man) or been subject of potential casting discussions (Peacemaker), it still seems highly possible King Shark will be in the movie.

However, the one casting rumor that circulated in May, that regular James Gunn collaborator Michael Rooker would play King Shark, was quickly denied by Rooker himself. No fresh casting rumors for who could play the character have emerged since.

MYSTERY CHARACTERS

benecio tel toro the collector marvel mcu guardians of the galaxy

Yondu and Drax's actors might not be in The Suicide Squad, but it looks like at least one Guardians cast member will be showing up. Benicio Del Toro, who played The Collector in the Marvel Cinematic Universe, is rumored to be looking to join Gunn's next film as a mysterious villain referred to as The General. Whether this is a codename for a specific comics character or not remains to be seen.

One role unearthed by Revenge of the Fans in casting notices has neither a name or any actors rumored for it yet. This role is described as "a monstrous femme fatale. A creature. A surly, muscular alien woman." Feel free to speculate on which characters this description could possibly refer to.