Magnum is tasked with guarding "Sir Algernon Farnsworth," a wealthy socialite's dog.
Higgins volunteers Magnum's services to guard a wealthy socialite's quarantined dog, after the attempted dognapping of the canine. Sir Algernon Farnsworth soon finds himself to be the most wanted dog in Hawaii, when his former owner, aging gangster Victor DiGiorgio, needs to get him back. Magnum and an animal regulations officer are soon on the run with Algie from the would-be dognappers -- and the fact that the officer seems to be scared of dogs doesn't exactly make matters any easier - but just why does DiGiorgio want the mutt back so badly?
- 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
- First episode to feature the Mike Post and Pete Carpenter Magnum P.I. theme music. It can be heard throughout the episode and over the closing credits from this episode onwards but it is not used yet over the opening credits until the episode number 12, Thicker Than Blood, which was its immediate answer.