Warning against writing details that could help the enemy in letters to servicemen.
Titles read: "THINK BEFORE YOU WRITE - A WARNING FROM AUSTRALIA".
M/S of a woman sitting at a desk, writing a letter. A photograph of a man sits on the desk.
Various shots show servicemen sorting large amounts of letters and parcels in a military post office. Commentator talks of strategic information being given away, unwittingly, to the enemy in letters.
Several shots of the Department of Mail Censorship workers going through letters. "Safe" letters are put in a box for immediate delivery; "Dangerous" ones are put in a box to "Hold For Treatment".
Sequence shows how a letter from a woman to a serviceman gives the enemy the cloaked information that a transport sailed just before dawn on Thursday. When the offending words are cut out of the letter, the other side is rendered unreadable. Several censored words are put together to illustrate how various hints in half a dozen letters can give vital information to the enemy.
Shots of torpedoes blowing up a warship at sea. Commentator says "It has already happened". C/U of newspaper articles saying letters could be to blame for the loss of a new ship.
End message of film is "Think before you write, or you may cause tragedy - even to your next of kin!".