Since the testing of the atomic bomb, most countries on earth have reported extensive sightings of unidentified flying objects, eighty per cent of which can be explained by man made or natural phenomena. Of the twenty per cent which are unexplained, many are verified by airforce pilots, airline pilots and radar recordings. In the USA, it is widely believed that actual craft and in some cases their occupants, have been secreted away for fear of public panic. With the aid of computer graphics and detailed reconstructions, this programme examines the likelihood of extra terrestrial visitations to the earth including the motives and likely purposes of such visits if indeed they have happened.
