David Harbour as Ernest

Jahi Di'Allo Winston as Kevin Presley

Anthony Mackie as Frank Presley

Erica Ash as Melanie Presley

Niles Fitch as Fulton Presley

Isabella Russo as Joy Yoshino

Tig Notaro as Dr. Leslie Monroe

Tom Bower as Ernest Scheller

Sean Boyd as Young Ernest Scheller

Nicholas X. Parsons as Fake Jesus

Steve Coulter as Deputy Director Arnold Schipley

Scott A. Martin as Sheriff Brown

Jennifer Coolidge as Judy Romano

Peggy Walton-Walker as Ramona Scheller

Sherri Eakin as Young Ramona

Faith Ford as Barbara Mangold

Yoshio Maki as Roy Yoshino

Sarah Voigt as Undercover Agent

Jophielle Love as Blonde Little Girl (Junebug)

Merah Benoit as Little Girl at Park

April McCullough as TV Publicist

Gabriel Sky as Kid #1 / "Family" #1

Taylor Shurte as Drunk Girl #1

Sarah Durn as Drunk Girl #2

Ariel Yasmine as Drunk Girl #3

Bob the Drag Queen as Vlogger (uncredited)

Major Dodge Jr. as Fulton Kid (uncredited)

Kyler Porche as Deputy Sheriff

Jo-Ann Robinson as June

Ned Yousef as Gas Station Clerk

Naoko Okamoto as Kumiko Yoshino

Mike Mayhall as Guard

Adam Stephenson as Scientist

K. Steele as Stoner (Lyft)

Lindsey G. Smith as Mom at Park

Shawn Sanz as Agent

Mary Alice Risener as Little Girl's Mother

Hawn Tran as Sound Mixer

Lara Grice as TV Producer

Seoum Tylor Aun as TV Camera Operator #1

Rob Mello as TV Camera Operator #2

Alasdair Flagella as TV Makeup

Cindy Pol as TV Hairstylist #1

Sylvia Grace Crim as TV Hairstylist #2

Brian Egland as TV Camera Operator #3

Phil McGraw as Dr. Phil

Ann Mahoney as H&R Block Woman

Jackson Kelly as Nerdy Freshman

Phuong Kubacki as H&R Block #2 (Coffee)

Lucy Faust as H&R Block Receptionist

Creek Wilson as Biker Dude

Turner Crumbley as Reporter #1

Billy Slaughter as Reporter #2

Erin McCluskey as Reporter #3

Stacie Davis as Reporter #4

Lena Clark as Reporter #5

Jordan Salloum as Reporter #6

Doug Spearman as H&R Block Client

Sherri Hamilton as Hair Stylist #3

Sarah Fisher as Staffer #3

Edgar Leza as Evanston Police Officer

Michael P. Sullivan as Crazy Book Fan (uncredited)