His role is still kept under wraps, but he may play one of the good guys and appear in both "Justice League Part One" and "Justice League Part Two", according to The Hollywood Reporter.
Dafoe, 60, is the second "Spider-Man" alum joining the DC team-up movie. Before the Green Goblin of Sam Raimi's webslinger trilogy is signed up, JK Simmons who played J Jonah Jameson in the Spidey film was tapped to portray Commissioner James Gordon.
The first "Justice League" is due in the US on November 17, 2017 and the second one is set for June 14, 2019.