Mr. Armitage has two pressing problems: the chemical company he owns has just developed a highly effective new nerve gas and has thus become the target of foreign governments' industrial espionage; and his stunning Swedish wife Utta is attracting far too much male attention.

Coming across an advert for the Upton Security company, he engages their services to oversee both keeping his factory secure and keeping an eye on his wife's movements. Unfortunately for proprietor Major Upton, he's hired all the wrong staff!

His newest recruit, Hobbs, is set to work on the latter challenge. It should be easy enough until he falls out of his treehouse lookout point and, found by Utta, quickly becomes enamoured of her charms!

The former task shouldn't be much more difficult, but a group of Japanese spies has already privately hired Upton's "number one" man, Hamilton, to obtain both a sample of the gas and copies of all paperwork related to its manufacture! Roping in his dogsbody, Gannet, to assist, the two first attempt to break into Armitage's home in the dead of night to steal the secret plans.

As Hamilton tries to hide his true endeavours from his boss, Gannet becomes trapped in the house for days on end. Upton is increasingly frustrated by a seemingly inexplicable series of setbacks, and Armitage becomes increasingly convinced Utta is now sleeping with the very men hired to keep an eye on her activities. But the Japanese are raising the stakes, Gannet falls in love, and Hamilton bribes an Upton colleague to hijack a delivery - all making for a very confusing final heist and getaway!