During 'Fall Out,' the former Prisoner known as No.6, is given a number of items one being the key to his house. However the former No.6 had no use for such a key, as the front door of his hoiuse had been given an "upgrade." In effect, the front door now operates in the same way as the door to his cottage, it opens automatically employing an electronic sensor.
Besides the Prisoner didn't enter his house, the butler did, while his master went off to hand in his letter of resignation. And yet by the time the Prisoner does return home to collect his two suitcases, wallet and travel documents, he does need his key to let himself into his house. So what happened to the upgrage of the door?
Be seeing you