When several sailors are trapped in a sunken battleship, the Oliver family is called on to rescue them. But Samuel's father and uncle are too big to move in the sunken boat. So Samuel…

The Oliver family take time away to explore an ancient cave. Samuel's father is keen on showing Samuel the cave, as his own father had done for him. The icy ascent to the cave's mouth is…

A German submarine has torpedoed the steamship Maiden. The damaged ship is an iron island in the sea. The Oliver family is called on to repair the vessel. Samuel sneaks off to prove to his…

After a long search, the Oliver family finds the sunken treasure ship they seek. But when they try to retrieve the fortune, a giant squid attacks! Can Samuel subdue the squid so his father…