Ruth Evershed

Occupation: Intelligence Analyst

Originally seconded to MI5 from GCHQ, Ruth quickly earned the respect of all her colleagues, sharing a special bond with Harry. Highly intelligent and meticulous, she provided the team with invaluable background research, drawing on an impressive range of facts. Her career at MI5 was cut short, when she was falsely accused of colluding with terrorists. Although Harry was prepared to go to prison to save her, Ruth took the blame, sacrificing the job she loved. Faking her death, she disappeared, leaving the world of MI5 behind. The Grid hasn't been the same without her, but now she's back.

Nicola Walker

Nicola's theatre credits include Gethsemane, Tales From the Vienna Woods, and Edmond, (The National Theatre), Relocated (Royal Court Theatre), Cloud Nine (Almeida Theatre), A Lie of the Mind (Donmar Warehouse). Previous TV credits include Turn Of The Screw, Grandma' House, Oliver Twist, Torn, Red Cap, People Like Us, A Dance To The Music Of Time, Moll Flanders. Her film work includes Shooting Dogs, Shiner, Four Weddings And A Funeral.