Watch Gaslight Full Movie Free Online 123Movies. Twenty years removed from Alice Barlow's murder by a thief looking for her jewels, newlyweds Paul and Bella Mallen move into the very house where the crime was committed. Retired detective B.G. Rough, who worked on the Barlow case, is still in the area and grows suspicious of Paul, who he feels bears a striking resemblance to one of Barlow's relatives. Rough must find the truth before the killer can strike again and reclaim his bounty.