Dramatisation of the science fiction novel by John Christopher. The end of the journey is in sight but there are still plenty of obstacles ahead. At the last of them, John has to make an agonising choice. Narrator ...... David Mitchell Pirrie ...... Bruce Alexander John ...... Darrell Brockis Ann ...... Rebecca Egan Roger ...... Gus Brown Ashton ...... Andrew Mayer Part of BBC Radio 4's Science Fiction Season.