Just after dawn in a secluded Cornish harbour, a member of the public reports seeing a tiny boat unload an unusual cargo into a waiting van. Police are soon in pursuit and make a shocking discovery.

Devon and Cornwall police officers face two very different manhunts: one featuring a high-speed runaway car and the other concerning a suicidal male in an abandoned tin mine.

Over one hectic weekend, rookie Chris finds himself in a dangerous high-speed car chase, ex-army Ash is tested by a pub brawl, and Katie confronts a gang of marauding football fans.