"Devious" Diesel, as his name implies, is a sinister diesel shunter who originates from British Railways, and is the first diesel engine to arrive on Sodor. In the television series, Diesel eventually becomes a permanent resident of Sodor.
A secret crew of LAPD comes together under the leadership of John O'Mara (James), a former World War II soldier, to tear down the world of one of the most dangerous gangsters, Mickey Cohen (Diesel), who runs the city.