This is a great movie, the kind of "oldie but goldie" which is worth to be rediscovered many years after the first viewing.
It has a good and smart story, very good action scenes which impress even today, 30 years after and last but not least, a STELLAR casting. Just count - Richard Burton, Roger Moore, Richard Harris, Stewart Granger and Harry Kruger, in all five stars. And then Jack Watson, a less known actor, who plays Master Sergeant Sandy Young - and with his size and his face he is simply the perfect incarnation of sergeant masterdom.
The story describes a rescue operation in a fictif African country - a major mining company wants to save an imprisoned African leader, hoping that once he seizes the power he will give them favourable terms on mining concession. The story is very similar to the archifamous Frederick Forsythe's novel "Dogs of War". This movie is however much much better than the adaptation of "Dogs of war" with Christopher Walken, especially because, although quite tragic, it has also quite a lot of hilarious moments and one-liners, many of them delivered by the gay medic serving in the unit.
A very good British war/adventure film, to discover or rediscover.