'iZombie' Season 4 Finale Features a Cameo From 'Ant-Man' Star Paul Rudd

Paul Rudd, best known to comic book fans for his role as Ant-Man in the Marvel Cinematic Universe, made a brief cameo appearance in tonight's season four finale to iZombie.

While the context of the "celebrity endorsement" changed over time, showrunner Rob Thomas actually tipped his hand a bit last year, while breaking down the premise of season four in an interview with ComicBook.com.

"We're going to pick up next season three months later, and the United States has walled off Seattle like it's West Berlin," Thomas teased. "Chase is hanging on by a very thin thread; it's like every day is the Cuban missile crisis. Brains are coming in, but they aren't getting as many as they expected, and zombies are hungry. In fact, the opening sequence in season four is going to follow a brain from the moment a man dies somewhere in Texas to the moment it reaches the brain tube and is ingested by a Seattle zombie. In fact, it's even going to start earlier than that. We're going to see a commercial on TV; we want to get someone like Laura Linney making a commercial pleading for the people of the United States to sign their brain donor card."

That Laura Linney thing is where Rudd came in this season: in order to sway public opinion away from Fillmore-Graves and save Liv, who had been scheduled for execution, Clive published Levon's documentary about the zombie underground railroad. It humanized Liv and made her a folk hero, and frightened Fillmore-Graves into thinking there might be riots if she was executed.

Once it started to go viral, someone at Fillmore-Graves shared a short clip of it with Chase Graves, who responded, "Is that Paul Rudd narrating the documentary?" When someone answered in the affirmative, Graves called Rudd "a good get."

Rudd played Desmond Fellows, a season 3 character on Thomas's series Veronica Mars. While some of the actors from that show have appeared in the flesh on iZombie -- most notably Jason Dohring, who plays Chase Graves -- some of Thomas's more famous alumni have chipped in by providing voice work. Kristen Bell provided the narration to an audiobook written by one of season two's murder victims.

iZombie will return for its fifth and final season next fall.