Edgar Rice Burrough's: The Land That Time Forgot

A yacht sets out for a long distance cruise with two couples (JASPER & CRYSTAL, young and newly married; and JOHN & AMY, older) and a small crew (captain, first mate, cook). A storm hits and the craft is struck by lightning and all navigation and electric goes out, the world turning to black…. They realize that they must have passed through the vortex known as the "Bermuda Triangle." Time itself is twisted, some having been there for years who disappeared a short time ago and others who disappeared long ago, just having arrived. Our heroes must join forces with the Germans to figure out a way to free the submarine and escape before they are all devoured. The survivors finally use the submarine to escape from the island, battling the plesiosaurus along the way. As they finally escape into the open sea, another storm strikes and the sub is buffeted by lighting and monster waves. The ship runs aground and they realize that they are back where they started. unable to escape the land that time forgot.