Three Cheers for the Irish is a 1940 comedy film directed by Lloyd Bacon, written by Richard Macaulay and Jerry Wald, and starring Priscilla Lane, Thomas Mitchell and Dennis Morgan. The supporting cast features Virginia Grey, Alan Hale, Sr. and William Lundigan. The plot involves a veteran police officer (Mitchell) forced into retirement only to learn that his replacement (Morgan), whom he detests, is romancing his daughter (Lane). The film was released by Warner Bros. on March 16, 1940.

Peter Casey is an Irish policeman in NYC with twenty five years on the force. He has three daughters Maureen, Pat, and Heloise. Maureen meets and falls in love with a Scottish policeman Angus Ferguson, Pat dates Ed Mckean, a wreaking supervisor who bores Peter and is a cheapskate, and Heloise who keeps time with a noted gambler- Joe Niklas. Peter unexpectedly gets retired after 25 years on the force and has to train Angus as his replacement to his disgust. Peter's police buddies buy him a rocking chair. In his retirement he get bored and has to deal with an overbearing friend, Gallagher. Worse, Angus has been dating Maureen behind his back. They even get married but keep it a secret. Over time Peter's friends run him for Alderman and despite Gallagher's overbearing help he wins the election. Peter, daughter and son-in-law work things when Maureen get pregnant. Angus chases Peter when as a good Catholic and Irishman runs looking for a priest to make the wedding official.