Camberwick Green was a children's animated television series that ran from 3 January to 28 March 1966. In 1967 and 1969, it was followed by "Trumpton" and "Chigley" respectively. By the early 1970s, it was still a popular children's programme, especially with young Sam Tyler. (LOM Series 2: Episode 5)
After becoming overdosed on hospital medication while in his coma in 2006, Sam Tyler became ill in 1973. While asleep in his flat, he began to hallucinate a version of Camberwick Green which involved him, his colleague DCI Gene Hunt and an unnamed "nonce".
The hallucination in the classic Camberwick Green introduction went as follows:
This is a box. A magical box. Playing a magical tune. But inside this box there lies a surpise.
Do you know who's in it today?
It's Sam Tyler. Hello Sam! How are you today?
Oh dear. Not very happy. Is it Gene Hunt? Is he kicking in a nonce?
Shortly after recovering from this hallucination but still suffering the effects of the overdose, Tyler received a phone call from DC Chris Skelton and DS Ray Carling who rang regarding Simon Lamb. Lamb threatened to commit suicide if they did not release Graham Bathurst.
When Tyler made it to the police station, Lamb was near to hanging himself from one of the lights of the cafeteria. As the police officers were persuading him not to hang himself, Sam told WPC Annie Cartwright briefly about his hallucination. When DCI Hunt entered the cafeteria, Sam told him threateningly to "stay out of Camberwick Green".