Complex sentence: Sly and Bentley recover Murray, who has been in hiding ever since Bentley's accident (which he blames on himself) and then go to find new members of the gang to help them in the heist of the Cooper vault.
Split into simpler sentences: Sly and Bentley recover Murray, who has been in hiding ever since Bentley's accident, which he blames on himself. The gang then goes to find new members of the gang to help them in the heist of the Cooper vault.