|On May 10, 1941, at about 6:00 P.M., Hess took off from Augsburg in a Messerschmitt Bf 110, and Hitler ordered the General of the Fighter Arm to stop Hess (squadron leaders were ordered to scramble only one or two fighters since Hess's particular aircraft could not be distinguished from others). Hess parachuted over Renfrewshire, Scotland on 10 May and landed (breaking his ankle) at Floors Farm near Eaglesham. In a newsreel clip, farmhand David McLean claims to have arrested Hess with his pitchfork.|
It appears that Hess believed Hamilton to be an opponent of Winston Churchill, whom he held responsible for the outbreak of the war. His proposal of peace included returning all the western European countries conquered by Germany to their own national governments, but German police would remain in position. Germany would also pay back the cost of rebuilding these countries. In return, Britain would have to support the war against Soviet Russia.
After being held in the Maryhill army barracks, he was transferred to Mytchett Place near Aldershot. The house was fitted out with microphones and sound recording equipment. Frank Foley and two other MI6 officers were given the job of debriefing Hess — or "Jonathan", as he was now known. Churchill's instructions were that Hess should be strictly isolated, and that every effort should be taken to get any information out of him that might be useful.
Hess became increasingly agitated as his conviction grew that he would be murdered. Mealtimes were difficult, since Hess suspected that his food might be poisoned, and the MI6 officers had to exchange their food with his to reassure him. Gradually, their conviction grew that Hess was insane.
Hess was interviewed by psychiatrist John Rawlings Rees who had worked at the Tavistock Clinic prior to becoming a Brigadier in the Army. Rees concluded that he was not insane, but certainly mentally ill and suffering from depression — probably due to the failure of his mission. Hess's diaries from his imprisonment in Britain after 1941 make many references to visits from Rees, whom he did not like and accused of poisoning him and "mesmerizing" him. Rees took part in the Nuremberg Trials of 1945.
Taken by surprise, Hitler had Hess's staff arrested. Questioning revealed that Hess was not motivated by disloyalty, but had simply cracked under the strain of the war. The official statement from the German government said that Hess had fallen victim to hallucinations brought on by old injuries from the previous war.
"My coming to England in this way is, as I realise, so unusual that nobody will easily understand it. I was confronted by a very hard decision. I do not think I could have arrived at my final choice unless I had continually kept before my eyes the vision of an endless line of children's coffins with weeping mothers behind them, both English and German, and another line of coffins of mothers with mourning children."
—10 June 1941 (from Rudolf Hess: Prisoner of Peace by his wife, Ilse Hess)
Hitler also stripped Hess of all of his party and state offices, and privately ordered him shot on sight if he ever returned to Germany. However, Hitler did grant Hess's wife a pension. Martin Bormann succeeded Hess as deputy under a newly-created title.