U.F.O

SHADO officially goes into operation and encounters its first UFO. An alien pilot is captured and discovered to have transplanted human organs within him.

When civilian test pilot Paul Foster inadvertently witnesses a SHADO operation, he is given a choice: join SHADO or die.

A SHADO interceptor pilot is placed under a hypnotic spell by an alien-influenced cat.

After Lunar Module 32 is mysteriously destroyed, Straker campaigns to have space junk removed from Earth's orbit.

Straker faces a terrible decision: attend to an alien defector or deliver life-saving medicine to his critically injured son.

A man with ESP knowledge of SHADO is co-opted by the aliens.

Foster and his lunar module co-pilot, Captain Frank Craig, are brainwashed by aliens to kill Straker.

A flashback episode focusing on SHADO's formation and how it caused the failure of Straker's marriage.

Straker must face his claustrophobia when the Skydiver submarine is damaged and unable to surface.

The aliens attack a Royal Navy destroyer that is dumping sealed containers of highly toxic nerve gas in the sea.

SHADO and an alien find themselves in the midst of a murderous romantic triangle.

Colonel Foster is tried and sentenced to death after a security leak is traced to him.

SHADO obtains what may be the first photos of the alien home world.

The aliens transform three humans into walking bombs.

Foster is stranded on the Moon, where he befriends a similarly stranded alien.

An alien crystal causes Lieutenant Andy Conroy, Straker and other SHADO operatives to hallucinate.

A blackmailed SHADO operative opens the door for a possible alien attack on Moonbase.

A SHADO pilot believed dead suddenly turns up alive - much to a SHADO operative's suspicion.

Communications problems at Moonbase are traced to a non-SHADO mining operation.

Time stands still at the film studio for everyone but Straker, Colonel Lake and a mysterious enemy.

A SHADO investigation reveals that romance may be complicating Moonbase operations.

The aliens abduct Colonel Foster.

A show jumper is abducted by the aliens.

The freighter 'Kingston' is sunk in mid-Atlantic by "flying fish" missiles and an underwater cameraman dies in mysterious circumstances.

Straker is attracted to a reporter who poses a possible security leak for SHADO.