Wealthy Rollo Treadway (Buster Keaton) suddenly decides to propose to his neighbor across the street, Betsy O'Brien (Kathryn McGuire), and sends his servant to book passage for a honeymoon sea cruise to Honolulu       When Betsy rejects his sudden offer however, he decides to go on the trip anyway, boarding without delay that night       Because the pier number is partially covered, he ends up on the wrong ship, the Navigator, which Betsy's rich father (Frederick Vroom) has just sold to a small country at war      　　Agents for the other small nation in the conflict decide to set the ship adrift that same night       When Betsy's father checks up on the ship, he is captured and tied up by the saboteurs       Betsy hears his cry for help and boards the ship to look for him, just before it is cut loose      　　The Navigator drifts out into the Pacific Ocean       The two unwitting passengers eventually find each other       At first, they have great difficulty looking after themselves, but adapt after a few weeks       At one point, they sight a navy ship and hoist a brightly-colored flag, not realizing it signals that the ship is under quarantine       As a result, the other vessel turns away      　　Finally, the ship grounds itself near an inhabited tropical island and springs a leak       While Rollo dons a deep sea diving suit and submerges to patch the hole, the black natives canoe out and take Betsy captive       When Rollo emerges from the ocean, the natives are scared off, enabling him to rescue Betsy and take her back to the ship       The natives return and try to board the ship       After a fierce struggle, Rollo and Betsy try to escape in a small dinghy       It starts to sink, and the natives swiftly overtake them in their canoes       Just when all seems lost, a navy submarine surfaces right underneath them and they are saved