Carol Hazell

World ecological collapse; the next ice-age has already begun! Lucky for us, governments know what to do. Unfortunately it's a conspiracy to end all conspiracies. Vanishing scientists, dubious space missions, and a freak accident which kills the courier of a tape containing a secret radio message from an unmanned Mars probe - holds the key. Ruthless investigative reporters uncover the ominous master plan. (imdb)

A trio of present-day children become involved in a conflict between a band of renegades and secret police from the 26th century (imdb)