The Last Witness (2)

Yasmina is dead, and Jane blames herself. The prime suspect has confessed and sits in jail, but Jane is certain he is not the real culprit, and certainly did not act alone. So she goes to Bosnia, against official advice, with her photojournalist friend Robert West, looking for the sadist she believes is responsible for so much death.

In Bosnia she meets her father, Arnold Tennison, who saw the camps in Nazi Germany as a young man and understands what Jane is looking for. Their focus falls on Milan Lukic, an optometrist who interprets for the suspect in custody. But Jane's questions draw the attention of officials who would rather she stopped; the Official Secrets Act is waved at her. Her father gives her the one clear moment of the trip, telling her how much he admires her for always doing what she believes is right.

Back in Britain, Duscan Zigic goes into hiding, an informer gives him up, and he confesses to killing both sisters. Jane remains convinced that Lukic and Zigic worked together. She is suspended, then summoned by Scotland Yard, made to sign the Official Secrets Act, and warned to stay off the case. A visit to her father settles it: she will stick to her convictions.

Peter Berry wrote it and Tom Hooper directed. Helen Mirren's Jane is supported by Oleg Menshikov as Milan Lukic, Ben Miles as DCI Simon Finch, Robert Pugh as DS Alun Simms, Clare Holman as Elizabeth Lukic, Mark Strong as DCS Larry Hall, Liam Cunningham as Robert West, Velibor Topic as Duscan Zigic, Barnaby Kay as DC Michael Phillips and Tanya Moodie as DC Lorna Greaves.

She keeps the promise she made to Yasmina, whatever it costs her. That has always been the bargain at the heart of the character, and the episode holds her to it.