Accused murderer Frankie Steele walks free, thanks to the efforts of San Francisco defense lawyer Joe Ricco. Then a pair of cop killings strikes the city. All signs point to the newly released Steele as the perpetrator. Has Ricco sprung a killer? Dean Martin keeps his affable ease but abandons his hipster Matt Helm-series swagger to portray Ricco in his final leading-role film, a whodunit mystery set in the city that also was the gritty center of action for the era’s Bullitt and Dirty Harry.