'Plan I' was a British deception plan to test whether or not the Germans placed sufficient trust in those of their agents, whom the British had 'turned', to plan and implement military operations on the basis of the 'information' passed to them by these double agents (January/March 1941).

In 'Plan I', the double agent known as 'Tate' passed to the Germans the 'information' that he had discovered an ammunition dump concealed in the New Forest. The British went so far as to construct a dummy dump, but there was no reaction from the Germans in the form of either reconnaissance or a bombing attack.