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After Yvonne's suspicions are aroused by Gary once again mysteriously heading off to far locations, Yvonne follows him and accidentally sees him in the act of vanishing into thin air as he steps through the time portal. In the past, Gary prevents an assassination attempt on future Prime Minister Clement Attlee, which leads to the time portal closing permanently, giving him no choice but to remain in the 1940s. He paints a final message to Ron and Yvonne on the same Mayfair flat wall from which Ron will one day strip old wallpaper, to discover the words. In an eerie scene, the words appear on the wall in the present as Gary scribbles them there in 1945.