North Sea Hijack is a movie about a group of men who claim to be reporters in Norway. They board an English supply ship and accompany them as they bring supplies to an oil rig and a production platform. However, once they arrive, they pull guns and take over the ship. They proceed to plant explosives on the rig and the platform.
They then contact one of the Prime Minister's people and threaten to blow up the rig unless they are paid what they ask for. The Prime Minister is advised to pay, but she is hesitant to give in to extortion. It is suggested that they contact Lloyd's to explore their options, and they discover Rufus Excalibur ffolkes, a man who has devised a plan to reclaim the rig.
One of the Prime Minister's people and an Admiral visit ffolkes, who explains his plan to go to the oil rig and board the supply ship as part of his strategy. However, the leader of the hijackers does not want ffolkes there and sends him back, complicating the plan.