CAST:
Ann Bell - Marjorie North
James Maxwell - Jock Ingram
Maurice Hedley - Ivor North
Robert Dean - Professor Soren
Robert McLeod - Professor Oakridge
Ronald Ibbs - Professor Walter Rand
Donald Bisset - Simms
James Copeland - Dr. Carey
Russell Waters - Thompson

Directed by Roy Baker; Screenplay by Terry Nation

STORY:
Templar is grouse hunting in the scottish moors. He soon hears of a laboratory which is located in this desolate region. When he walks home through the moors he has an encounter with a man with protective clothing who uses an unknown ray weapon. Back at his quarter he is introduced by his host Ivor North to Professor Oakridge and security man Jock Ingram who both work at the research facility.
Now first one of North's men gets killed in a strange fashion, then Oakridge is found murdered in the laboratory. With his own blood he was still able to write three letters: COP. Is Ingram really the murderer?

NOTES:
* Ann Bell also appears in Episode #89 "The Art Collectors"
* James Maxwell also appears in Episode #89 "The Art Collectors"
* Robert McLeod also appears in Episode #15 "Judith"
* Ronald Ibbs also appears in Episodes #32 "The Lawless Lady" and #64 "The Abductors"
*  There is an obvious cut right after the light from the weapon goes off. (0:07)

AIRDATE:
UK: 28th January 1965