Watch Sherlock Season 3, Episode 3 His Last Vow Online

Some stolen letters leads Sherlock Holmes into a conflict with Charles Augustus Magnussen, the Napoleon of blackmail, and the one person he truly hates. A case of stolen letters leads Sherlock Holmes into a long conflict with Charles Augustus Magnussen, the Napoleon of blackmail, and the one man he truly hates. But how do you tackle a foe who knows the personal weakness of every person of importance in the Western world? Sherlock has to face his biggest challenge yet when he has to give a Best Man's speech at John's wedding. Mortal danger stalks the reception though and somebody might not make it to the happy couple's first dance. Two years after the devastating events of ‘The Reichenbach Fall’, John appears to have got on with his life. New horizons and romance beckon. But, with London under threat of a devastating terrorist attack, Sherlock is about to take John at his word, staging his resurrection with all the theatricality that comes so naturally to him. If Sherlock thinks everything will be just as he left it, though, he’s in for a very big surprise…