West Berkshire, the 1970s. PC Don Barton is convinced that life has taken a turn for the better when he passes his promotion exam and becomes an acting sergeant. Things take a turn for the worse after a violent altercation with a local thug. Soon later, Don finds himself investigating a hit-and-run case. Somehow, international drug smugglers and the London gangland all seem to be involved. Don is determined to find out the truth, but...