The British Board of Film Classification (BBFC) has accidentally revealed a major villain's appearance in Batman and Superman: Battle of the Super Sons.

The BBFC has given the upcoming DC animated film a 12-rating for moderate violence, threat, bloody images and implied strong language. The organization explained its decision under the film's rating information, which goes into specific detail on what led to the film earning a certain rating. Under injury detail, the BBFC stated that "there is occasional bloody detail, including a slow-motion blood spurt in the aftermath of a punch. Alien starfish explode bloodily." The threat and horror section additionally mentions the inclusion of "moderate body horror when alien starfish erupt from victims' mouths. Two young teenagers must fight their possessed parents." With the mention of both alien starfish and possession, all signs point to Battle of the Super Sons featuring popular Justice League supervillain Starro.

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Created by writer Gardner Fox and artist Mike Sekowsky, Starro the Conqueror first appeared in The Brave and the Bold #28 in 1960 and was the first villain to face the original Justice League of America. The character made its live-action film debut in James Gunn's 2021 film The Suicide Squad, which was set in the DC Extended Universe. The DCEU's version of Starro is capable of growing larger and more powerful depending on how many people it has possessed at once. The character was killed in the film by the remaining members of the Suicide Squad, including Bloodsport, Harley Quinn, King Shark, Polka-Dot Man, and Ratcatcher 2.

Batman and Superman: Battle of the Super Sons was announced at DC Fandome in Oct. 2021 and will be the first installment in the DC Universe Animated Original Movies line to use CGI. Jon Kent and Damian Wayne are assumed to be the titular super sons, who must join forces in the film to save the planet. The BBFC additionally revealed that the film will star Jack Dylan Grazer, Jack Griffo and Laura Bailey, but it is unknown at this time who the actors will be playing.

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The DC Universe Animated Original Movies have been a consistent performer for Warner Bros. Home Entertainment since its inception in 2007 with the release of Superman: Doomsday. The series has been mostly well-received by fans and critics. In addition to Battle of the Super Sons, upcoming films in the series include Green Lantern: Beware My Power, which is set in the same animated shared universe that began with 2020's Superman: Man of Tomorrow, and an untitled Milestone Media film, featuring characters from the comic imprint.

Batman and Superman: Battle of the Super Sons does not yet have an exact release date but is scheduled to be released this fall.

Source: BBFC