I've always felt that John Wayne did his two police films McQ and Brannigan for a combination of reasons. Some of his last westerns before these like The Train Robbers and Cahill were really not up to standard and didn't get the reception at the box office Wayne films could usually expect. I also think those rugged western locations were becoming a problem healthwise. And of course Wayne was bowing to the public's new taste in heroes.
In McQ Wayne is investigating the death of his partner, the way Humphrey Bogart investigated the shooting death of Jerome Cowan in the Maltese Falcon. He has to go private to do it, he actually resigns from the Seattle PD and gets a private license, courtesy of a friend, David Huddleston. The investigation leads him to some surprising and not welcome conclusions.
John Wayne is always the great symbol of law and order and at first glance you would think this might not be a role for him, investigating crooked cops. But when you think about it in films like Tall in the Saddle and Rio Lobo he dealt with crooked sheriffs in the usual Wayne manner. In fact the whole point of Rio Lobo is Wayne putting his whole life on hold to find a couple of guys who betrayed him and their country during the Civil War. So McQ is definitely in line with both of those films.
In the supporting cast my favorite is Al Lettieri the drug kingpin of Seattle. Lettieri's death a few years after this film was a great loss to cinema. During the first half of the Seventies, ever since playing Virgil Sollozzo in The Godfather, Lettieri created some really outstanding villains and Manny Santiago here is one of them.
The ending will surprise you and its more Maltese Falcon than you would think.
