Il cast Between Two Ferns: Il film
- Zach Galifianakis as himself
- Lauren Lapkus as Carol Hunch
- Ryan Gaul as Cameron “Cam” Campbell
- Jiavani Linayao as “Boom Boom” De Laurentis
- Edi Patterson as Shirl Clarts
- Rekha Shankar as Gaya
- Mary Scheer as Frannie Scheindlin
- Mary Holland as Gerri Plop
- Matt Besser as Mike Burcho
- Phil Hendrie as Bill Yum
- Paul Rust as Eugene Tennyson
- A. D. Miles as Michael
- Blake Clark as Earl Canderton
- Paul F. Tompkins as Burnt Millipede
- Demi Adejuyigbe as DJ Fwap
- Mandell Maughan as Nic Jeffries
Nel ruolo di sé stessi
Awkwafina, Chance the Rapper, John Cho, Benedict Cumberbatch (Avengers: Infinity War – Colonna Sonora Film 2018), Peter Dinklage, Will Ferrell, Gal Gadot, Tiffany Haddish, Jon Hamm, Rashida Jones, Brie Larson, John Legend, David Letterman, Matthew McConaughey (Cast Cocaine – La Vera Storia di White Boy Rick), Keanu Reeves (John Wick 3 – Parabellum), Paul Rudd, Jason Schwartzman, Adam Scott, Hailee Steinfeld, Chrissy Teigen, Tessa Thompson, Bruce Willis, Phoebe Bridgers, Matt Berninger e Walter Martin.
Le musiche originali della colonna sonora sono compose da Alex Wurman, noto soprattutto per le musiche de La marcia dei pinguini, Anchorman: The Legend of Ron Burgundy, Talladega Nights: The Ballad of Ricky Bobby e la serie televisiva Patriot. Nel film sono presenti anche alcuni brani di repertorio, tra i quali è ricorrente il tema del film del 1976 diretto da Martin Scorsese Taxi Driver.
I titoli di tutte le canzoni del film Between Two Ferns: The Movie
1. Taxi Driver – Theme – Bernard Herrmann
2. It’s Real – Paris
3. In The Corner, At The Table, By The Jukebox – James Hand
4. Soul Dance – Houston Person
5. Baby, Baby, Don’t Tell Me That – James Hand
6. The Treatment – Ohmega Watts
7. Walking On A String – Matt Berninger’s Serpentine Prison featuring Phoebe Bridgers
8. Walking On A String (Alt) – Matt Berninger’s Serpentine Prison featuring Phoebe Bridgers