The BBC has released the first picture from the new series of Sherlock. The sleuth has enlisted the services of a bloodhound to track someone down...

The first image from the new three-part series of BBC1’s Sherlock has been released – and Sherlock Holmes appears to have enlisted the services of a bloodhound.

Bloodhounds are renowned for their ability to follow human scents over great distances, but with no more information available, the question is – who is Sherlock (Benedict Cumberbatch) trying to locate or track?

Filming on the three feature-length episodes of series four began in May and one of the storylines involves Doctor Watson (Martin Freeman) and his wife, Mary (Amanda Abbington), preparing for their biggest challenge – becoming parents for the first time.

Co-creators and writers Steven Moffat and Mark Gatiss commented: “Sherlock series four – here we go again! Whatever else we do, wherever we all go, all roads lead back to Baker Street – and it always feels like coming home.

“Ghosts of the past are rising in the lives of Sherlock Holmes and John Watson bringing adventure, romance and terror in their wake. This is the story we’ve been telling from the beginning. A story about to reach its climax…”

Sherlock and bloodhound