An American movie company wants to shoot a science-fiction film using a British army barracks as a location, and its soldiers as actors.
| Actor | Role |
|---|---|
 Brian ReeceCapt. Bill Harper | Capt. Bill Harper |
 Margot GrahameWanda Sinclair | Wanda Sinclair |
 Raymond HuntleyCol. Fred Bellamy | Col. Fred Bellamy |
 Sidney JamesEd Waggermeyer | Ed Waggermeyer |
 Tony HancockLt. Wilfred Cartroad | Lt. Wilfred Cartroad |
 Peter SellersPvt. Goffin | Pvt. Goffin |
 Clive MortonGen. Sir Cuthbert Grahame-Foxe | Gen. Sir Cuthbert Grahame-Foxe |
 June ThorburnVeronica Bellamy | Veronica Bellamy |
 Maureen SwansonJoanne Delamere | Joanne Delamere |
 Peter MartynLt. John Broke | Lt. John Broke |
 Bill FraserPvt. Slee | Pvt. Slee |
| EEdward LexyCapt. Ledger | Capt. Ledger |
 Barry MacKayR.S.M. Benson | R.S.M. Benson |
 Donald PleasenceCpl. Martin (as Donald Plesance) | Cpl. Martin (as Donald Plesance) |
 Eric SykesPvt. Waterhouse | Pvt. Waterhouse |
 Michael TrubshaweA.D.C. | A.D.C. |
| MMaureen PryorMiss Marigold | Miss Marigold |
 Donald HewlettLincoln Green | Lincoln Green |
 Reginald HearneSgt. Spurway | Sgt. Spurway |