Ralph Meeker as Mike Hammer

Albert Dekker as Dr. G.E. Soberin

Paul Stewart as Carl Evello

Juano Hernández as Eddie Yeager

Wesley Addy as Lt. Pat Murphy

Marian Carr as Friday

Maxine Cooper as Velda

Cloris Leachman as Christina Bailey

Gaby Rodgers as Lily Carver

Nick Dennis as Nick

Jack Lambert as Sugar Smallhouse

Jack Elam as Charlie Max

Jerry Zinneman as Sammy

Leigh Snowden as Cheesecake

Percy Helton as Doc Kennedy

Marjorie Bennett as Manager

Strother Martin as Harvey Wallace

John George as Popcorn Vendor (uncredited)

Fortunio Bonanova as Carmen Trivago

Nat King Cole as Self - Singer (voice)

Kitty White as Club Vocalist

Mady Comfort as Nightclub Singer

Art Loggins as Bartender (uncredited)

Robert Sherman as Gas Station Man (uncredited)

Eddie Beal as Sideman (uncredited)

Leonard Mudie as Athletic Club Clerk (uncredited)

Mort Marshall as Ray Diker

James McCallion as Horace

Robert Cornthwaite as FBI Agent

Silvio Minciotti as Mover

Ben Morris as Radio Announcer

Paul Richards as Attacker

Jesslyn Fax as Horace's Wife

James Seay as FBI Agent

Sam Balter as Radio Announcer (voice)

Joe Hernandez as Radio Announcer (voice)