McQ (1974)

Synopsis
Undoubtedly having second thoughts after turning down Dirty Harry, John Wayne showed up in 1974 in his own "maverick cop" adventure, McQ. Wayne, playing McQ, a veteran detective, turns in his badge when he's officially denied the opportunity of clearing the name of his late best friend, who has been posthumously accused of drug pushing. Investigating on his own, McQ becomes romantically involved with his friend's widow (Diana Muldaur), who unbeknownst to him is up to her neck in police corruption. Considering the usual flag-waving content of John Wayne's 1970s films, it is rather startling to discover that the real villains in McQ are a coterie of crooked cops! ~ Hal Erickson, All Movie Guide