Legendary U.S. lawman Bat Masterson is in Toronto and claims to have seen the equally legendary Butch Cassidy and the Sundance Kid. Masterson is now a newspaperman and he's already filed a story about the sighting with his New York paper. Murdoch is doubtful about the whole thing and is under the impression that Butch and Sundance had fled to Argentina the previous year. Brackenreid is keen however - and just a bit starstruck - and they set off to find the two men Masterson says he saw. After the Bank of Toronto is robbed - and that quickly followed by a train robbery - Masterson's claims appear confirmed. Masterson himself thinks otherwise and comes clean. Meanwhile, Julia and William's wedding day is fast approaching but they have yet to select just where they will be married. Julia has an idea however. The men of Station 4 plan Murdoch's bachelor party.

The sudden death of a key witness leaves Murdoch physically unsettled.