Martha Costello is now a QC, but she learns fast that it can be lonely at the top. At Shoe Lane Chambers times are tough, and senior clerk Billy struggles to keep things afloat while Clive Reader tries to be stoic about his unsuccessful silk application. Martha is defending Brendan Kay, a member of one of London's biggest crime outfits. He is accused of blinding a man, who allegedly disrespected their 'number two'. Martha's job is made harder because Brendan's solicitor, Micky Joy, is an old school player of the system who walks both sides of the line. Also up against a notorious QC, Caroline Warwick, nicknamed Lady MacBeth for her uncompromising approach in court, Martha feels herself pulled by the various political forces around her, and realises to win she will need an all or nothing defence. Meanwhile, Clive takes on a sensitive case with a new solicitor, George Duggan.
Martha Costello is 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.
Joining Martha is Clive Reader. 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.