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?

Written by Steven Moffat, ‘His Last Vow’ airs at 8.30pm on Sunday 12 January on BBC One and CultBox was lucky enough to attend a preview of the episode at BAFTA in London last night. To whet your appetite, here are ten teasing lines of dialogue from the episode…

» “This is blackmail.”

» “What case could possibly justify this?”

» “You do not own me.”

» “Stay out of my bedroom.”

» “One more push.”

» “No, we’re not playing this game.”

» “I was waiting until we were married.”

» “Red beard.”

» “I have an excellent memory.”

» “Who’s Sherlock Holmes?”

> Find out all the details on Series 3 in our news summary.

Are you looking forward to ‘His Last Vow’? Let us know below…

> Order Series 3 on DVD on Amazon.

> Buy the Series 1-2 boxset on Amazon.

Watch the Series 3 teaser trailer…