With Blackwood hanging dead from the Tower of London, Holmes sees to Irene, having been pushed off the platform by Blackwood. She is unharmed, so Holmes (remembering her previous words: 'I don't want to run anymore') cuffs her, and waits for the police. In the meantime, Irene reveals that the mysterious man for whom she was working was Professor Moriarity. He found my weak spot, Irene admits, and warns Holmes not to underestimate Moriarity in the future. Holmes chuckles, put the key to the handcuffs down Irene's bodice, takes the diamond pendant from around her neck, and kisses her goodbye. Some days later, as Watson arrives with Mary to move out of 221B (look for the diamond pendant now appearing as an engagement ring on Mary's finger), Watson and Mary find Holmes hanging from a ceiling noose, trying to discover how Blackwood managed to survive the hanging. Holmes deduces that he used a hook and a body harness to take the weight off his neck and a serum made from the Rhodedendron ponticum to induce paralysis, which is why Watson could feel no pulse. In the final scene, Constable Clark (William Houston) stops by to inform Holmes that one of their officers was found dead in the sewers, killed by a small-gauge bullet between the eyes. Holmes deduces that Moriarity created the diversion with Irene, knowing that Holmes would chase after her, so that he could steal the part of the chemical converter that allowed it to be activated by radio waves. Realizing that Moriarity might be as clever as Irene described him, Holmes puts on his hat and declares, 'Case reopened.'