Series 3 began filming this week and sees Luther “under intense pressure, with two conflicting crimes to investigate and a ruthless ex-copper determined to bring him down”.

The synopsis reads: “Luther’s life is his job; that is, until love crosses his path and offers him a chance of happiness.”

Guillory will play a character named Mary, who works in a vintage clothes shop and meets Luther in a chance encounter.

The Eragon actress commented: “You realise why Luther is so good when you read Neil Cross’s scripts, and then you meet Idris and understand what ‘untamed’ means. There is no other set I’d rather be on, and I love the disastrous fun of being Mary Day, the right girl in the wrong place.”

Idris Elba, who plays Luther, added: “I want to thank the fans for waiting so patiently for the new season. We’re thrilled to deliver it to you. Here comes John!”

Alongside returning cast members Warren Brown (Good Cop) as DS Justin ‘Ripley’, Nikki Amuka-Bird as DS Erin Gray, Dermot Crowley as DSU Martin Schenk and Michael Smiley as Benny Deadhead, guest stars will include Lucian Msamati (Game of Thrones) and Ned Dennehy (Parade’s End).

It was confirmed earlier this month that Series 3 will comprise “four perfectly dark, chillingly-formed episodes”. The four 60-minute episodes will air on BBC One in 2013.

Are you looking forward to Series 3? Let us know below…

> Order Series 3 on DVD on Amazon.

> Buy the Series 1-2 boxset on Amazon.

Watch the trailer for Series 2…