A shootout at a city hotel leaves young Ukranian nanny Sofia Teplov dead along with an unknown hitman.
Russian oligarch Maksim Bazhanov was the target, but how has he managed to escape the attack?
Nikki and Jack work with young DI Sarah Parks to identify the dead hitman and try to discover who wants Bazhanov dead.
It's difficult when they find out the hitman is ex-army, putting the number of paymasters who could have hired him as much higher.
Meanwhile, Jack is drawn to Sarah, whose daughter had a rare childhood cancer, and is impressed by how she juggles work and family.
Silent Witness, BBC, 9pm
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