Tough as that challenge was, the illusionist always claimed that it was a Birmingham U.K locksmith called Nathaniel Hart, who gave him the most challenging test that he had ever faced.
Harry Houdini was appearing to packed houses at the London Hippodrome, in March 1904.
Issuing his customary invitation for challenges to the audience. Dozens had come forward with assorted shackles and handcuffs that the self-styled "Handcuff King" managed to slip out of with astonishing ease.
In front of a packed matinee audience, the great man was again presented with the Hart handcuffs. At first he attempted to get out of the challenge by claiming that he only attempted to escape from regulation police handcuffs, but after a lot of persuading he relented. So it was that on March 17th he went on the stage of a packed Hippodrome theatre to a standing ovation from 4,000 fans. Houdini approached the front of the stage and addressed the audience "I do not know whether I am going to get out or not. But I can assure you I am going to try my best".
Houdini then disappeared into his stage cabinet, which he named his "ghost house", to begin his historical escape as the band under the direction of Mr Georges Jacobi began to play. After twenty two minutes he poked his head out of the cabinet, in order to get a better look at the lock in the strong lights of the theatre. When the clock reached thirty five minutes Houdini again emerged from the "ghost house" with his stiff collar broken and sweat pouring down his face. He complained that his knees hurt and requested a cushion on which to kneel. The handcuffs however remained in place. After another thirty five minutes he emerged again, to groans from the now restless audience. The shackles were still in place. Houdini asked the man from the Daily Mirror if he would remove the cuffs in order for him to take off his coat. The reporter refused, so Houdini took a pen knife from his pocket, flipped his jacket over his head and cut it to ribbons. Determined to free himself from the Hart handcuffs, Houdini returned to the "ghost house" for a final attempt.
Failure was not an option, the great escapologist was at this time at the height of his fame, and to fail would see his credibility and career ruined. In addition the Daily Mirror, which was one of the most widely read newspapers of the day, would run the story of how the great Houdini failed in his attempt to free himself from a pair of British made handcuffs. Such headlines would see its sales rocket.
Ten minutes later, and with the band reaching a soaring crescendo, Houdini emerged triumphantly holding the handcuffs aloft for all to see. After an hour and ten minutes, he had managed to escape. The crowd went wild, waving their hats and handkerchiefs in the air. One man dashed forward from the milling throng and lifted Houdini up onto his shoulders and paraded him around the theatre.
The Daily Mirror later presented Houdini with a silver replica of the Hart handcuffs. He responded by sending the paper a telegram saying "I must say it was one of the hardest, but at the same time one of the fairest tests I have ever undertaken". Nothing more has been reported of the Birmingham locksmith Nathaniel Hart, the man who invented the unpickable handcuffs and who almost beat the Great Houdini.