I didn't know the DVDs were out already...

Wikipedia: Do Not Adjust Your Set "(DNAYS) was a children's television series produced originally by Rediffusion, London, then by the fledgling Thames Television for British commercial television channel ITV from 26 December 1967 to 14 May 1969. (...) This was an early appearance of many actors and comedians who later became famous, such as Denise Coffey and David Jason; Michael Palin, Terry Jones, and Eric Idle later became members of the hugely successful Monty Python's Flying Circus. (...)The programme comprised a series of sketches, often bizarre and surreal, frequently satirical with a disjointed style which was to become more famous in the more daring Monty Python's Flying Circus, which followed five months later."

Amazon: “Do Not Adjust Your Set” (2 DVDs)

Some clips on YouTube

Wikipedia: At Last the 1948 Show: "David Frost personally approached John Cleese, Graham Chapman and Tim Brooke-Taylor, to star in a new television sketch series, and they suggested to him that Marty Feldman, who had been known only as a comedy writer (primarily for radio) up to then, be included in the cast. The series represented an important stage between the radio cult series of I'm Sorry, I'll Read That Again and the television cult series Monty Python's Flying Circus and The Goodies, as well as leading to Marty Feldman's television comedy sketch series Marty (which included Tim Brooke-Taylor in the cast), when the conventional light entertainment format in which wacky comedy scenes were interspersed with popular songs was finally abandoned. "

Amazon: “At last the 1948 Show”(2 DVDs)

Some clips on YouTube

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