When Lt. Tanaka is murdered while participating in a drug deal, it is up to Magnum to find his killer and prove his friend's innocence in the process.
- Tom Selleck as Thomas Sullivan Magnum IV
- John Hillerman as Jonathan Quayle Higgins III
- Roger E. Mosley as Theodore "T.C." Calvin
- Larry Manetti as Rick Wright
- Kwan Hi Lim as Lieutenant Yoshi Tanaka