As a retired caver and former member of a cave rescue team I found this programme quite outstanding. Rarely if ever has caving been so convincingly shown at such a high technical level. Even though one knows the outcome of this rescue, it is hard to imagine how challenging it must have been. But equally challenging is assembling a record of the rescue with such authenticity. I assume that all the footage was shot at the time by members of the rescue teams, but stand corrected if that was not the case. Whatever, the incredibly high technical standard of the underground filming was astounding, especially when compared with earlier 16mm caving docs, and footage shot on head cams. The rescue is very effectively intercut with interviews and commentary, primarily from the surface and underground rescue co-ordinators. Only when I read the credits on IMDB did I realise that the part of George the vuctim was played by an actor. Or was he......? An outstanding achievement.