03 Feb 2017 10:36 PM +00:00 UTC

Mark Hamill Finally Fights Beside Batman in Justice League Action

Mark Hamill, whose voice-over of the animated Joker remains one of the best interpretations of that character, finally fights by the side of Batman in an upcoming episode of Justice League Action. A new video clip released by DC shows Hamill voicing the Swamp Thing, the so-called immortal "god of the green" who can control all plant life on Planet Earth.

But the Swamp Thing finds himself outflanked by another unkillable character, Solomon Grundy, who has recruited a zombie army to conquer the world. So the incarnation of ecology does the one thing that the Joker might not do: ask Batman for help. The Caped Crusader obliges, bringing in Constantine and Zatanna for the ride.

Watch the clip below.

Justice League Action's episode, "Zombie King," will air on February 4, 2017 at the Cartoon Network.