Lee Martin's The Midnight Hour: Sinistique (7.4)
Shop worker Darryl is assaulted in an "accident" by colleague Billy after witnessing Billy and his girlfriend in flagrante delicto. Left with a potentially deadly brain injury, his tormentors begin to die of cerebral hemorrhages similar to what he may soon experience himself, leading to an investigation stymied by Darryl's indisputable alibis.