72 Hours Season 1 Episode 13 Monster of Miramichi

Firemen are called to put out a blaze and discover two sisters, one dead and the other on death's door. Detectives learn that a man snuck into the house late at night and brutally sexually assaulted the sisters before setting fire to the house. The attacker's face was covered with a balaclava and he had a chain around his waist that could have been part of prison shackles.