In the film, Miriam Grant (Rosamund Pike) and the 2nd Mrs P (Minnie Driver) both attended McGill University. Ironically, out of all three actresses to play Barney's wives, it is the actress playing Clara (Rachelle Lefevre) who is an actual graduate of McGill University.
Four noted Canadian film directors make cameo appearances in the film. We see Atom Egoyan as a director of O'Malley of the North, Ted Kotcheff as the conductor on the train, David Cronenberg as another of O'Malley's directors, and Denys Arcand as the head waiter at the Ritz. And, although better known for their acting, Paul Gross and Saul Rubinek are also movie directors.
Paul Gross who plays Canadian Mountie Constable O'Malley of the North also played a Canadian Mountie, Constable Benton Fraser, on a popular TV series known as "Due South" [1994-1999] and having him play the Mountie in this film may be seen as an "in joke."