Merchant seaman Skitch Kilroy (Jackie Cooper) and "Pappy" Reagan (Jackie Coogan)arrive in Marseilles, eager to resume their combative rivalry for Mimi. But they are ordered by their skipper Muldoon (Ralph Sanford) to remain on board and guard against theft of foodstuffs by a black market gang.
Fed up with the sea, Paul, a Swiss mechanic working in the noisy bowels of a merchant ship, lands in Lisbon.
Sailors Pike and Shorty are on leave when a street woman swindles them out of some money by telling them she is looking for her long-lost brother, a sailor.
A pair of sailors are on shore leave - skirt chasing and raising hell. They're targeted and pursued by a gang looking for a sailor with a winning lottery ticket. Mayhem ensues.
The Stooges join the war effort by enlisting at Merchant Marines. While aboard, they have a brief run-in with (a secret German Nazi officer) Lt. Dungen (Vernon Dent), and then mistake a torpedo for a beached whale. Moe says they have to kill it, and it promptly explodes. After being lost at sea for several days, they come across the SS Schicklgruber and climb aboard. Now with fully grown beards, they come across Lt. Dungen again, who does not recognize them. After realizing they are on a German war ship they eventually overtake the crew and toss them overboard.
In Tiger Bay, the docklands of Cardiff, rough-and-tumble street urchin Gillie witnesses the brutal killing of a young woman at the hands of visiting Polish sailor Korchinsky. Instead of reporting the crime to the authorities, Gillie merely pockets a prize for herself — Korchinsky's shiny black revolver — and flees the scene. When Detective Graham discovers that Gillie has the murder weapon, the fiery young girl weaves a web of lies to throw him off course.
A German living in India during World War II is blackmailed by the English to impersonate an SS officer on board a cargo ship leaving Japan for Germany carrying a large supply of rubber for tyres. His mission is to disable the scuttling charges so the captain cannot sink the ship if they are stopped by English warships.
A merchant marine captain, rescued from the Chinese Communists by local visitors, is "shanghaied" into transporting the whole village to Hong Kong on an ancient paddle steamer.