Undertone (1)

When the body of a pregnant Northern Irish girl is discovered, the team face the urgent task of finding the baby snatched from her womb. The child's father, married man Simon, is the prime suspect in DS Sally Kirchner's eyes.

Meanwhile, Thomas uncovers the teenage girl's connections to a criminal underworld. Nikki and Jack encounter her addict boyfriend Nuri and ruthless drug dealer Bekir, suspected of masterminding the killing of a Drugs Squad cop. The dead detective's partner, DI John Brooke, is out to avenge his colleague's murder.