The film, which debuts, September 20, is written by Galifianakis and Scott Aukerman (who is also directing). The premise is as follows: After Will Ferrell discovered his public access TV show "Between Two Ferns" and uploaded it to Funny or Die, Galifianakis became a viral laughing stock. Now, he and his crew are taking a road trip to complete a series of high-profile celebrity interviews and restore his reputation.
Rumored guests include Bradley Cooper, Ed Helms, Keanu Reeves, Peter Dinklage and Letterman.
The last episode of the Funny or Die series featured Jerry Seinfeld, Wayne Knight and Cardi B and premiered in June 2018. Previous guests have included President Barack Obama and former Secretary of State presidential candidate Hillary Clinton.
Here are a couple more images from "Between Two Ferns":