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 Lamb struggles to keep things afloat while Reader tries to be stoic about his unsuccessful Silk application.
Costello represents Captain Ed Ryan in a court-martial. He's accused of disobeying direct orders, resulting in the death of a 19-year-old private. Under the watchful eyes of a distraught family who want answers, Costello navigates the army's legal system with the help of Captain Cassidy, Ryan's unit defence officer. Doggedly seeking the truth, Costello slowly peels back the layers of past and present wounds, revealing the shocking reality of modern combat. Meanwhile, temptation is never far away for Reader, who is warned by Lamb to keep his relationship with Duggan purely professional.
Reader is in Oxford, prosecuting three students accused of sexually assaulting a waitress. Up against an intimidating defence counsel, he begins to waver, but a chance encounter with an old friend helps him discover a passion for prosecuting he didn't know he still had. When the case is in danger of collapsing, Reader is faced with one of the biggest decisions of his career.
Costello finds herself in a David v Goliath battle when she represents the driver of a high-security prison van. When some of his prisoners escaped, Michael Ward opened the doors to find another dead. With Ward and the security firm accused of causing the prisoner's death, Costello fights to make Ward stand up for himself, lest he becomes the fall guy.
At the Supreme Court, Costello is representing Jackson Henderson in a death row case. Against a ticking clock and with Lamb breathing down her neck, she faces the toughest legal argument of her career. Meanwhile, Reader increasingly feels that he is not the right barrister for Fatima Ali and, at the risk of losing Duggan, persuades Costello to take the brief, conveniently leaving him free to prosecute Jody Farr.
Reluctantly representing Farr, Costello vows to do her job, but she will not allow him or Micky Joy to get under her skin. Fighting shifting power plays and an untenable defence, she begins to feel that Farr is not getting a fair trial and suspects foul play. Setting a dangerous trap, can Costello uncover the unbelievable truth?