Maxine Peake (Criminal Justice), Rupert Penry-Jones (Spooks), Natalie Dormer (The Tudors), Tom Hughes (Sex, Drugs And Rock And Roll) and Neil Stuke (Reggie Perrin) star in Silk, a thrilling new drama series for BBC One about the lives, loves and hard cases facing barristers on the front line of criminal law, written by Bafta award-winning writer Peter Moffat (Criminal Justice, North Square).

Maxine Peake is Martha Costello, in her thirties, single, passionate and a defence barrister applying for silk. Innocent until proven guilty are four words she lives by. But how does this fundamental principle stand up to examination by clients who are sometimes good, sometimes bad and sometimes evil?

Martha is faced with challenging cases and surprising clients. Her beliefs and prejudices, her conscience and her faith in the criminal justice system are tested to the limit over the course of the series.

Former barrister Peter Moffat makes a return to BBC One, providing an insider's view into this exciting, morally complex, highly-charged world.

Peter says: "Silk is based on my experience at the bar. I want to tell it as it really is. The extreme pressure, the hard choices, the ethical dilemmas, the overlap between the personal and the professional, principles fought for and principles sacrificed, the Machiavellian politics, the sex, the drinking, the whole story – life at the bar is the richest possible drama territory."

Joining Martha is Clive Reader, played by Rupert Penry-Jones. He's funny, gifted and dangerous. The same age as Martha, they're called to the bar together. Both are applying for silk – how they perform in court is vital to this process and Clive knows how to play the game.

Neil Stuke plays Billy, the senior clerk at Martha's chambers. He is dedicated to Martha, even if secretly he believes that she hasn't got a chance of being made a QC.

Nick Slade, played by Tom Hughes is Martha's pupil. Niamh Cranitch (Natalie Dormer) is assigned to Clive. Both are thrown in at the deep end and, as "baby barristers", must sink or swim. Only one pupil will be taken on as a member of chambers at the end of the series. Who will it be and why? And how will Martha and Clive influence the outcome?

Silk was commissioned by Jay Hunt, Controller, BBC One and Ben Stephenson, BBC Controller of Drama Commissioning. The executive producer is Hilary Salmon (Criminal Justice, Five Days).

Ben Stephenson says: "Bafta-winning writer Peter Moffat marks his return to BBC One with a brilliant new legal drama series, which takes a modern look at the genre. Maxine Peake and Rupert Penry-Jones lead an incredible cast and star as amibitous barristers competing for much coveted Silk."

Silk is directed (episodes 1 & 2) by Michael Offer (The Passion, Moses Jones) and is produced by Cameron Roach (Life On Mars, Moses Jones).

The new six-part drama will commence filming in July. Silk will follow in the footsteps of successful BBC dramas such as Criminal Justice, Five Daughters and Luther.

The term "silk" originates from the connotations linked with being a QC (Queen's Counsel). "Silk" comes from the idea that when a barrister is made a QC they will be given authority to wear coloured robes. Traditionally, these robes were always made of silk. QCs are well known to be the most senior barristers who are also the most experienced and highly ranked in their field.