John Delaney had been on his way home from a ratting match at the local pub and somehow ended up face down in the river. When Murdoch finds the drunken body of his estranged father, Harry, passed out near the crime scene, he's quick to convict the man he's long accused of killing his mother. It turns out that the matches were fixed - just like Harry said - and the detectives seem to be closing in on the case. But when evidence turns up that suggests Delaney may have had a rendezvous after leaving the pub that fateful night, the investigation takes a whole new turn.