Episode 4

The Unit's war of attrition on Roach and his gang is beginning to take effect - under pressure, and low on drugs and money, they're forced to turn to a new foreign supplier, a Norwegian nicknamed the Viking. The Unit know how vital the Viking could be in learning more about the crew they're targeting, but he's proving frustratingly hard to pin down. Clever and terrifyingly ruthless, the Viking thwarts the Unit at every turn, and the team find themselves at odds with each other about the best way to proceed. If they fail this time, the city will be flooded with a tonne of dangerous drugs, and Roach will be a step closer to achieving his ambitious expansion plans.