The detectives investigate an assault which turned to murder after the victim died of his injuries. Twin brothers were known to have forced their way into a vulnerable man's home in Hull, punching and kicking their way in before savagely attacking him. Police and dog handlers were quickly on the scene thanks to a 999 call from the victim and soon caught the attackers after a chase. But could they gather enough evidence to charge the brothers with murder - and work out which twin threw the fatal punch?