- Country: UK
- Genres: Documentary, Short
- Release: 2010-10-04
- Director: Paul Vanezis
- Writers: N/A
- Language: English
- Stars: Matthew Sweet , Nicola Bryant , Martin Cochrane , Peter Davison
- Runtime: 36 min
- Awards: N/A
- AKA: Chain Reaction (United Kingdom) , Chain Reaction
- Plot: For the special features of the Special Edition DVD release of the story, cast and crew look back at the making of Doctor Who: The Caves of Androzani: Part One (1984).
- IMDB:tt7292946