While Willem Dafoe starred in the first Aquaman, there's a simple reason he's not returning to the DCU film.

“Willem is not in this one, no,” Aquaman and the Lost Kingdom director James Wan told Entertainment Weekly. “Part of the reason was because his schedule did not work out for us. But what that allowed me to do was expand on Atlanna's (Nicole Kidman) role. Atlanna in this one ultimately becomes Arthur's (Jason Momoa) advisor. Because Arthur's not from this world, she helps him better understand the world and the politics of how things work.”

It's not as if Dafoe has been out of work, though. Since Aquaman, Dafoe has starred in the likes of The Lighthouse, The French Dispatch, The Card Counter, Spider-Man: No Way Home, Nightmare Alley, The Northman, and Asteroid City. He also starred in Poor Things, which just premiered at the Venice Film Festival and will release later this year.

Coming up, Dafoe will star in Beetlejuice 2 and will reunite with The Northman director Robert Eggers' Nosferatu remake.

Earlier in his career, Willem Dafoe starred in the likes of Platoon, The Last Temptation of Christ, Faraway, So Close!, American Psycho, and Sam Raimi's Spider-Man.

Aquaman and the Lost Kingdom sees the titular hero's rise to power in Atlantis. This causes new threats to arise, including Black Manta (Yahya Abdul-Mateen II). Patrick Wilson, Dolph Lundgren, Randall Park, Nicole Kidman, Temuera Morrison, and Amber Heard all reprise their roles from the previous film. James Wan returns to direct the DCU film.

Aquaman and the Lost Kingdom will be released on December 20.