An estimated 9.2million viewers tuned for the highly-anticipated return of Sherlock on New Year's Day.
Fans of the show were left stunned after last season's finale which saw Sherlock, played by Benedict Cumberbatch, apparently plunging to his death. Teasers for the new series revealed that he was alive, prompting widespread speculation as to how he faked his death.
The episode teased viewers by exploring the theories, including a guest appearance from Derren Brown. "Ah yes, Sherlock, of course. Timeline is going berserk," he tweeted. "Pleased you enjoyed my cameo. (And trust you hated them and me for just a second…)".
The episode prompted more than 300,000 tweets, including the hashtag #SherlockLives which also featured on the show.
"It's brilliant to be back," said Benedict. "Fans won't be disappointed," he added.