Sherlock series 3: 'His Last Vow' trailer released

The Sherlock finale is already upon us, and looks to be a much darker episode

Sherlock and Holmes in the 'Sherlock' series 3 finale 'His Last Vow' (BBC)

The trailer for the finale of Sherlock series three has been released by the BBC.

Scroll down to see the trailer

The three episode-long series finishes with “His Last Vow”, which looks to be much darker than the previous two episodes.

In the series three finale, Sherlock faces up to new super villain Charles Augustus Magnussen, played by The Killing’s Lars Mikkelsen.

In the 30-second trailer, Sherlock says: “I’ve dealt with murderers, psychopaths…none of them can turn my stomach like Charles Augustus Magnussen.”

But Mycroft is seen telling younger brother Sherlock: “You go against Magnussen, you’ll find yourself going against me.”

Last night’s episode “The Sign of Three” divided opinion, with some enjoying the flashbacks from Watson’s wedding while others commenting on the lack of solid plot.

His Last Vow airs on BBC1 at 8.30pm on Sunday 12 January