Merchant marines have their ship sunk by a German submarine, but they ship out again in a convoy and get revenge on their way to Russia.
Captain Steve Jarvis (Raymond Massey) tells Lt. Joe Rossi (Humphrey Bogart) to get his toothache fixed and orders Cadet Robert Parker (Dick Hogan) to double the watch. Sailors Boots O'Hara (Alan Hale), Abrams (Sam Levene), and others discuss women. Pulaski (Dane Clark) says the gas cargo is dangerous. A German submarine torpedoes the ship twice. Amid fire and explosions they abandon ship. Germans on the sub film the lifeboat and ram it. Men swim to the raft. Jarvis swears vengeance. Planes search for eleven days and then find them.
Rossi says he will ship out again. Jarvis is welcomed by his wife (Ruth Gordon). Rozzi uses alcohol on his tooth. A man talks of troop ships, and Rozzi knocks him out. Rozzi meets singer Pearl (Julie Bishop). At the union hall Pulaski says he wants to stay with his wife but ships out with the others. Parker is assigned to Jarvis's ship again. Jarvis asks Rozzi to go with him and learns he is married. Rozzi says goodbye to Pearl.
A gun crew reports to the ship. Ensign Wright makes them practice and teaches the crew. They take on more cargo in Canada and join a convoy of 73 vessels with the Navy. Captain Williams explains their positions. Jarvis tells Rozzi they are going to Russia. Rozzi talks with Pulaski about fear and courage. German submarines attack the convoy, and they sink a German ship. The convoy is dispersed, and O'Hara says they will get together again. They see planes, which attack them. They shoot back and are bombed. They shoot down a plane, but Jarvis is strafed. Pulaski helps load a gun. A plane crashes into the ship, and Parker dies. Rozzi gives Jarvis a pain pill and removes the bullet. Rozzi has Pulaski pack Parker's things. Rozzi conducts the funeral for eight men. Rozzi learns they only have half speed. A submarine torpedoes them. Rozzi orders fires set so that the sub will surface, and the ship rams the sub. Rozzi orders the fires put out. They see Russian planes and enter Murmansk. Women call them comrades. The voice of President Roosevelt says materials will be delivered for victory.
This propaganda war drama portrays the camaraderie of
the merchant marines that ship the weapons and supplies to the