Gas and Oil: Part 1

S5 E1: Drama about the British Security Service returns. A terror attack on a gas and oil depot has led to energy rationing and people dying of cold. Amid rumours of further terror threats, the team discovers that intelligence about the attack was ignored by MI6. It soon becomes clear that, far from being a foreign threat, a team of insiders are attempting to take control of the government through a number of terror attacks.