A sleek, fast-paced BBC hit focusing on domestic-security intelligence agents, dealing with threats that range from arms merchants to germ warfare. The series had a cast overhaul in its third season, with three lead agents replaced by husband-and-wife operatives who came from MI-6.
First Aired: September 22, 2006
Conclusion. Adam rescues Tash from the terrorists, with Tash's help, and realizes that the top priority is to find the mole in MI-5. Meanwhile, Ruth tries to protect Prof. Curtis after a second attempt on his life. Tash: Martine McCutcheon. Lydia: Ania Sowinski. Forster: Andrew Tiernan.