This a two-part special that is half documentary-styled and half a story to go along.
In part 1, the main cast from the show discuss what it was like filming the series and how the series came to be in existence.
In part 2, as the cast is filming an episode, Cruella interrupts and captures the puppies by doing some TV hijacking, so it is up to the uncaptured members to save them before its too late.
This was inspired by the 101 Dalmatians: The Series episode "The Making of..." and the 1988 film Who Framed Roger Rabbit. It is also inspired by TV incidents such as the Max Headroom incident. By the way, this episode is non-canon to the actual series.