production

• Roger Corman — producer
• Peter Cornberg — production supervisor
• John C. Broderick — associate producer
• Jerome L. Posner — location coordinator

sound

• David Grisman — original music composer
• David Grisman — music
• Robert Gravenor — sound mixer
• Lowell Brown — boom operator
• Samuel C. Crutcher — assistant sound editor
• Gene Corso — sound effects designer

directing

• Steve Carver — director
• Jann Carver — script supervisor
• Eugene Mazzola — assistant director
• Teri Schwartz — assistant director

writing

• Howard Browne — writer

crew

• V.R. Bud Shelton — property master
• Roger George — special effects
• Steve Ferry — property master
• Charlie Picerni — stunt coordinator

art

• Ned Parsons — set decoration
• Ward Preston — art direction
• Stephen R. Ferry — property master

costume & make-up

• Maurice Stein — makeup artist
• Patricia Miller — hairstylist

editing

• Richard C. Meyer — editor
• Barbara Meyer — assistant editor

camera

• Héctor R. Figueroa — camera operator
• Vilis Lapenieks — director of photography
• Robert Edesa — first assistant camera

lighting

• Lee Heckler — lighting director

Reparto

• Ben Gazzara — Al Capone
• Harry Guardino — Johnny Torrio
• Sylvester Stallone — Frank Nitti
• Susan Blakely — Iris Crawford
• John Cassavetes — Frankie Yale
• Frank Campanella — Big Jim Colosimo
• John Orchard — Dion O'Banion
• Carmen Argenziano — Jack McGurn
• George Chandler — Robert E. Crowe
• John Davis Chandler — Hymie Weiss
• Royal Dano — Anton J. Cermak
• Joe De Nicola — Charles Fischetti
• Angelo Grisanti — Angelo Genna
• Peter Maloney — Jake Guzik
• Dick Miller — Joe Pryor
• Robert Phillips — Bugs Moran
• Martin Kove — Pete Gusenberg
• Mario Gallo — Giuseppe Aiello
• George Milan — William H. Thompson
• Russ Marin — Joseph Stenson
• Tony Giorgio — Antonio Lombardo
• John Martino — Tony Amatto
• Bert Conway — Frank Loesch
• Don Pulford — William Cooper
• Pamela Toll — Mrs. Atkins
• Eugenia Stewart — Miss Detwiller
• Don McGovern — N.Y. Cop #1
• Redmond Gleeson — N.Y. Cop #2
• John Finnegan — N.Y. Police Lt.
• Laurence Hagen — Samuel Ettelson
• Tom Cook — Sam Volenta
• Vincent Barbi — Solly
• Tina Scala — Mrs. Torrio
• James V. Christy — Thomas Bronk
• Jack Ackerman — Adam Heyer
• Ralph James — Judge J.H. Wilkerson
• Carmen Filpi — Waiter
• Jim Galante — John May
• John Howard — Warden J. Johnston
• Beach Dickerson — Joe Kepka
• John C. Broderick — Maitre d'
• Chuck Traynor — Senator
• James R. Sweeney — Prison Doctor
• George Engelson — Torrio's Doctor
• Deborah Klose — Female Reporter
• John Favorite — First Reporter
• John Armond — Second Reporter
• Jack O'Leary — Pool Hall Owner
• Ben Marino — Frank Gusenberg
• Vincent Di Paolo — Mob Soldier (uncredited)