Who does Misha Collins play in The Boys? Meet Malchemical

Misha Collins — best known as Castiel from 15 seasons of Supernatural — appears in The Boys season 5 as Malchemical, a supe with a spectacularly unpleasant superpower.

Who is Malchemical?

Malchemical can generate and breathe out toxic chemicals and gases. In the comics by Garth Ennis, Malchemical is a prenatal supe (meaning he was exposed to Compound V in the womb) and a member of the high-profile superhero Team Titanic. His comic book powers go further — full molecular and matter manipulation, making him a dangerous shapeshifter.

The show streamlines this. TV Malchemical is essentially a walking chemical weapon who can knock out even Homelander with a concentrated blast of poisonous breath. He's crass, chaotic, and clearly enjoying the end of the world more than he should.

What happens to him?

Malchemical appears in episode 5, "One-Shots," alongside Jared Padalecki's Mister Marathon in a segment following Soldier Boy (Jensen Ackles) and Homelander in Los Angeles. The three Supernatural leads are reunited on screen for the first time since Supernatural ended.

Malchemical and Marathon confront Soldier Boy and ask him to help kill Homelander. Soldier Boy refuses. In the ensuing fight, Soldier Boy chokes Malchemical to death. Marathon lasts longer but is ultimately killed by Homelander, who stomps on his head.

Collins' screen time is brief but memorable. Showrunner Eric Kripke (who also created Supernatural) confirmed the casting was deliberate fan service — a chance to bring the three leads together one more time in the most chaotic way possible.