The Jensen Code

The Jensen Code
Title card
Written by	Carey Harrison
Directed by	Alan Coleman Jonathan Wright Miller
Starring	Dai Bradley Tony Wright
Country of origin	United Kingdom
Original language(s)	English
No. of series	1
No. of episodes	13
Production
Producer(s)	Alan Coleman
Running time	25 minutes
Production company(s)	ATV
Release
Original network	ITV
Original release	28 February – 23 May 1973

The Jensen Code is a UK children's television adventure series. Produced in colour by Associated Television (ATV) in 13 installments, it originally aired weekly on the ITV network between 28 February 1973 and 23 May 1973. It was written by the novelist and dramatist Carey Harrison (son of actor Rex Harrison).

The story begins with 16-year-old Terry Connor sat alone in a cavern 100 feet underground whilst on a potholing expedition. The senior outward bound instructor, Alex, has long since been missing in the depths of the cavernous subterranean pot named 'Wilmer Deep' after going to retrieve a torch which Terry had dropped earlier. When Alex returns (without the torch) he is strangely convinced that he has been away for ten minutes but Terry knows that Alex has been away for more than two hours. Alex believes that Terry has suffered hallucinations, which he says can be a side-effect of the confined darkness of an underground cavern. When they surface Terry believes he has seen man watching them, to which Alex again suggests it is an hallucination and that Terry is not cut out for potholing and so should not go on the big potholing expedition on which the rest of the students will be going the next day. Returning to the outward bound centre, Terry is subjected to much ribbing by his fellow students including the ring leader Jacko. Terry is convinced that the centre or the students at least, are being watched and when the others inform Terry that there is a Ministry Of Defence research establishment nearby he begins to feel increasingly uneasy. Another instructor at the centre, Gordon, becomes aware of Terry's concerns and tells him that he believes his story that Alex had gone missing for two hours but that he can't say much more than that.

The following day, Terry is detailed to go on his own day and night solo trek above ground. However, eager to prove to himself that he is unafraid of the cave, Terry sets out to return to Wilmer Deep. First, he needs to obtain the key to the gate which covers the cave and that key is kept at Granny Powell's farmhouse. When Terry turns up there he is unexpectedly joined by Alex, who is accompanied Kurtz, the man Terry had seen spying on them the previous day. Strangely, Alex appears vague and seems to have no recollection of setting Terry the trekking task.

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