Context: Doug (Barry Sullivan) and Helen Stilwin (Barbara Stanwyck) head off for a fishing vacation with their son Bobby (Lee Aker). Doug wants to return to beach he visited years before. The family is towing a small trailer with camping gear so they can fish and camp on the isolated beach south of Escondido in Mexico.As they leave drive, they get farther away from towns, services, and civilizations. When they need water for the cars radiator, they can only find a deserted service station. They leave the main road and encounter a police block. After a quick scan of the car, the Mexican authorities let them proceed, with no explanation for why they were stopped. When Helen asks Doug why he didn't push for an explanation, he tells her he didn't want them to look too closely at the car. He didn't want to explain why he was carrying his army pistol. Helen puts the gun in the glove box and they proceed.When they arrive at the beach, it is indeed isolated. An old, rotting jetty emerges far out into the water. As Doug and Helen are getting settled in and relaxing, Bobby climbs out to the jetty's end. Helen is worried the jetty is not safe and frantically calls Bobby back. As he return, his foot slips and is caught between two planks. Doug goes out to free him. As they are walking back over the precarious timbers, a large wave combined with Doug's weight causes the jetty to fall. Doug is trapped on the beach, his foot stuck under a timber too large to move.Helen tries to dig Doug out with a shovel, but the beach is solid rock. She retrieves the car jack and nearly has the large timber raised when the pin in the jack breaks. Doug and Helen decide that with a sturdy rope, she can pull the timber with the car. Helen will have to drive back to the deserted service station to find a rope. They estimate that Helen should have four hours before the rising tide covers Doug completely, threatening to drown him. Bobby stays with Doug and makes him a cup of coffee. Bobby tries unsuccessfully to wave down a fishing boat. When all hope is nearly gone, Doug and Bobby have a serious father and son talk about what should happen if Helen does not return in time.Helen races down the road. When she encounters a Mexican family, she pleads for help or a rope, but they do not understand her poor attempt at Spanish until she is gone. She reaches the service station and breaks into the building and retrieves a rope. As she returns to the car, she is relieved to see Lawson (Ralph Meeker), an American man, suddenly standing by her car. She quickly enlists his help and they head for the beach to save her husband. As they pull away with Lawson in the drivers seat, the camera shows a dead man lying in the bushes.Lawson soon reveals that he has no intention of helping her husband. He is running from the police. He finds the gun in the glove compartment and holds the gun on her while they pass the police. While he is speeding down the rough roads, they have a flat tire. Lawson is unable to find the jack, but manages to drive the car up onto a ramp made of abandoned boards. After he changes the tire, Helen tries to hit him with a tire iron, but he is able to fight her off. He escapes capture again, but this time has to fire the gun at a police car pursuing him. Realizing that she cannot overpower Lawson, Helen begins to bargain with him. Helen promises Lawson her husband's clothes, his identification card, and the car if only Lawson will help free her husband. Finally, she offers him what he really wants: she will go with him after they free his husband. Traveling as couple and with her husband's identification, they will more easily get by the police. She will do anything to save her husband's life.Once they arrive at the beach, the situation is dire. The rising tide 
 Question: Who plays the role 'Bobby'?
Output: lee aker