The war is over and now the US Navy is preparing for the next one, that will likely involve guided missiles. Commander Talbot (Glenn Ford) is keen to get his submarine involved in these new trials after watching an early missile (basically a V-2) launched off an aircraft carrier.
The trial will involve firing V-1s off the decks of submarines, things don't go easy of course and involve the crew of the submarine in various troubles, Talbot is also trying to a girl (Viveca Lindfors)...
The film is a bit slow, and is at times it a little too much like a piece of propaganda but the early missile footage is very interesting.