The cancelled sequel to Marvel‘s The Incredible Hulk would have included the on-screen debuts of the Red and Grey Hulks, it has been revealed.

Speaking to Comic Book, Louis Leterrier – who directed 2008’s The Incredible Hulk – revealed details about the Edward Norton-starring sequel that was ultimately cancelled by Marvel.

“There was, like, a whole sequel,” Leterrier said, adding that the scrapped film would have featured variations of the Hulk. “There was, like, Grey Hulk, Red Hulks — there was a lot of good stuff that we were planning.”

Grey Hulk, in the comic books, was a mutation of Bruce Banner’s Hulk powers, combining Banner’s brains with Hulk’s strength. The character was a lot more serious and sarcastic in the source material when compared to the Marvel Cinematic Universe‘s Smart Hulk, who leaned more towards comedy.

“Hulk is a complex character within the Marvel Universe,” Letterier explained. “You want the primeval Hulk… the rage Hulk. And then when you go Grey Hulk and Smart Hulk you lose that a little bit and you get a little bit more kiddish with it.”

2008’s The Incredible Hulk starred Edward Norton as Bruce Banner/The Hulk, Tim Roth as Abomination and Liv Tyler as Betty Ross. Mark Ruffalo would go on to entirely replace Edward Norton as The Hulk in the Avengers franchise from 2012 onwards.

In other news, Marvel most recently released a new trailer for The Marvels, which is due to release in November. The Marvels will be the next entry in Phase Five of the Marvel Cinematic Universe, which kicked off earlier this year with Ant-Man and the Wasp: Quantumania and continued with Guardians of the Galaxy Vol. 3.