Steve Martin as Dr. Michael Hfuhruhurr

Kathleen Turner as Dolores Benedict

David Warner as Dr. Alfred Necessiter

Paul Benedict as Butler

Richard Brestoff as Dr. Pasteur

James Cromwell as Realtor

George Furth as Timon

Peter Hobbs as Dr. Brandon

Earl Boen as Dr. Felix Conrad

Bernie Hern as Gun Seller

Francis X. McCarthy as Olsen

William Traylor as Inspector

Randi Brooks as Fran

Bernard Behrens as James Gladstone

Natividad Vacío as Ramon

David Byrd as Desk Clerk

Adrian Ricard as Nurse in Room

Sparky Marcus as Bellboy

Perla Walter as Housekeeper

Mya Stark as Little Girl

Don McLeod as Dr. Schlermie Beckerman / Gorilla

Peter Elbling as Morgue Attendant

Kate Sarchet as Hooker #2

Wendy Sherman as Hooker #3

Tom Spratley as Minister

Estelle Reiner as Tourist in Elevator

Jeffrey Combs as Dr. Jones

Jenny Gago as Nurse #1

Haunani Minn as Nurse Breen

Stepfanie Kramer as Beautiful Girl Hit by Car

George Fisher as Patrol Car Officer

Merv Griffin as The Elevator Killer

Bob Harks as Lecture Guest (uncredited)

Sissy Spacek as Anne Uumellmahaye (uncredited) (voice)