Sherlock Lives: Series 3 trailer makes surprise debut

The BBC has released a tantalisingly brief trailer ahead of Benedict Cumberbatch and Martin Freeman's return in the third series of Sherlock.

With the hashtag #SherlockLives featuring prominently, the teaser gives a glimpse of what is ahead in the hit reboot of Sherlock Holmes:

The surprise offering was shown after Doctor Who's 50th anniversary special The Day of the Doctor.

An air date has yet to be announced, with the teaser only revealing Sherlock is "coming soon".