The Acorn Syndrome

A government engineer gets the phone call every parent dreads. His daughter has been taken, and the price of her safe return is the defence secrets he works on. It is the oldest lever in the espionage book, and it works because the man at the other end is a father first. Every hour he hesitates is an hour his daughter stays in the hands of people who have already killed.

The case finds its way to CI5 through a couple of hired guns shot after a hostage situation. The trail leads to the Apex arms factory, where an employee called John Copeland is being blackmailed into copying plans for a new tank and handing them to East German agents. From there it is a stalk across country to a remote farmhouse, where the girl is being held and a shoot-out is waiting. The kidnapping and the industrial espionage turn out to be the same crime, which is the neatest thing about the setup.

Brian Clemens and John Kruse wrote it, Martin Campbell directed. Ronald Hines is Copeland, with Lynda La Plante as Viv Copeland, which is worth mentioning on its own: La Plante went on to create Widows and Prime Suspect, and it is fun to spot her here as an actress. Michael Craig is Guthrie, Ian Redford is Lucas, Alun Lewis is McCabe, Oona Kirsch is Sandy Copeland and Kate Dorning is Nancy.

The blackmail plot is straightforward, but the episode keeps its nerve by staying close to the people. Copeland is a decent man being crushed between his family and his country, and the show does not let him become a plot device. Every decision he makes hurts someone, and the script lets that weight sit on him rather than rushing past it.

A solid season opener, tense in the right places and smart about its villain, which is a fair way to begin a new run of episodes.