Tom Selleck

Thomas Magnum, Sebastian Sabre, Dashiell Hammett

John Hillerman

Jonathan Quayle Higgins, Father Paddy McGuinness, Jonathan Quayle Higgins III

Roger E. Mosley

Theodore 'TC' Calvin, Winston, Inspector Wolf

Larry Manetti

Orville 'Rick' Wright, Ziff, Reverend Myron Bentley

Gillian Dobb

Agatha Chumley, Mabel, Nona Barnes

Kwan Hi Lim

Lieutenant Yoshi Tanaka

Jeff MacKay

Lieutenant McReynolds, Jim 'Mac' Bonnick, Ski

Kathleen Lloyd

Carol Baldwin, Bridget Archer

Glenn Cannon

Dr. Ibold, Dr. Bernard Kessler

Patrick Bishop

Keoki, Pat, King Kamehameha Club Attendant, Attendant

Elisha Cook Jr.

Francis 'Ice Pick' Hofstetler, Wilmer, Harold W. Farber

Lance LeGault

Colonel Buck Greene, Agent John W. Newton

Jean Bruce Scott

Lt. Cmdr. Maggie Poole, USN, Lieutenant Maggie Poole, USN

Clyde Kusatsu

Police Detective Lt. Gordon Katsumoto, Dr. Long Tang, Naval Medical Examiner

Elissa Dulce Hoopai

Rosine, Vicki (Waitress), Tiffany

Marta DuBois

Michelle Hue, Michelle, in flashback

Phyllis Davis

Cleo Mitchell, Magnum's 1940's Secretary, Tiffy, Magnum's Secretary

Esmond Chung

Police Sergeant Kenny Chung, Peter (Tour Guide), Honolulu Police Officer