This film was inevitable as the late '60s -- following Paul Newman's hit "Harper" (1966) -- reinvented the '40s-'50s private eye yarn by adding more sex and violence. GUNN fits somewhere in the middle of this trend -- not as classy as "Harper" and "Deadlier Than the Male", not as cynical and gritty as Sinatra's "Tony Rome" films (1967-68). Craig Stevens, with his wry humor and effortless charm, rises above the material, much like James Garner in "Marlowe" (1969) -- a highly recommended film in this genre.
Old school "Peter Gunn" fans will lament the absence of Lola Albright and Hershell Bernardi (a cranky Ed Asner fills in), but this should be seen on its own terms as a stand-alone film. The opening credits, with psychedelic graphics and jazzed up theme music, suggest a 007 spy film influence, but the story is a standard whodunit with gangsters and frequent murders. Some of these killings (like the diver with the spear gun) and plot turns don't make much sense or are needlessly complicated, but the fast pacing and supporting cast distracts one from worrying about the details. The sex appeal quotient is ramped up considerably by gorgeous Sherry Jackson (sadly, stunning Carol Wayne only has a cameo at the end). Jackson even did a Playboy pictorial to promote the film. And, for an added plot twist, writer-director Blake Edwards indulges in his strange obsession with gender bending (Victor Victoria, Switch, et al,).
All in all, this is a slick, breezy, enjoyable detective yarn that moves along with strategically placed scenes of action, humor, and eye candy. It is very much a product of the late '60s. (Will someone please release this, along with "P.J." and "Rogue's Gallery", on disc already?) In the next decade this genre would get darker and more complex with The Long Goodbye (1973), Chinatown (1974), and Night Moves (1975).