James Gunn and Warner Bros. debuted the first, R-rated trailer for “The Suicide Squad” on Friday, and it’s clear the foul-mouthed supervillain spectacular doesn’t skimp on all manner of bad behavior.

The main story is still out of reach, but the trailer opens with a mission to rescue Margot Robbie’s Harley Quinn that proves unnecessary, as Harley already got herself out of whatever scrape she found herself in.

One of the biggest revelations, however, is that Sylvester Stallone is providing the voice for King Shark, who is, basically, a man with a shark head (or, possibly, a shark with a human body).

Oh, and then there’s the giant, colorful starfish kaiju who begins to rampage at the end of the trailer.

“The Suicide Squad” is something of a sideways sequel to 2016’s “Suicide Squad.” Several of the first film’s stars are reprising their roles, including Margot Robbie as Harley Quinn, Viola Davis as Amanda Waller, Joel Kinnaman as Rick Flag, and Jai Courtney as Captain Boomerang. And Gunn has said his film’s story is not a reboot of the original movie.

But Gunn — who wrote and directed Marvel Studios’ two “Guardians of the Galaxy” movies — is also bringing a much livelier, 1970s-war-movie tone, not to mention a cavalcade of new characters, to the story of DC comics supervillains who are conscripted to save the world after their incarceration.

First among the new rogues is John Cena as Peacemaker, an ends-very-much-justify-the-means vigilante who believes himself to be a hero (but whose brutal methods suggest otherwise). Gunn is already in production on a prequel series about Peacemaker for HBO Max, starring Cena, Danielle Brooks, Chris Conrad, Jennifer Holland, Steve Agee, Robert Patrick and Chukwudi Iwuji.

The ensemble for “The Suicide Squad” also boasts Idris Elba as Bloodsport, David Dastmalchian as Polka-Dot Man, Alice Braga as Sul Soria, Daniela Melchior as Ratcatcher 2, Nathan Fillion as T.D.K., Mayling Ng as Mongal, Michael Rooker as Savant, Pete Davidson as Blackguard, Peter Capaldi as Thinker, Sean Gunn as Weasel, and Flula Borg as Javelin.

“The Suicide Squad” will open on August 6 in theaters and on HBO Max.

Watch the trailer below.