Pat O'Brien: Pat O'Brien. Actor: Some Like It Hot. Although he came to be called "Hollywood's Irishman in Residence"--and, along with good friends James Cagney, Allen Jenkins, Frank McHugh and a few others were called "The Irish Mafia"--and he often played Irish immigrants, Pat O'Brien was US-born and -bred. As a young boy the devoutly Roman Catholic O'Brien considered entering the seminary to study for the priesthood, but although he often played...