It is the 21st Century. The first manned flight to Mars is about to begin. At the vast complex known as Glenn Field five men are ready to embark on Earth's most dramatic step to space exploration.

For pilot Paul Travers, co–pilot Greg Martin and Space Navigator Brad Newman this is the climax of months of tense and vital training.

With the three astronauts will travel space scientists Doctors Grant and Pierce. Their vehicle will be the fantastic ZERO X . . . the most advanced space ship ever designed.

The seconds tick past . . . the controller checks his systems . . . the scene is set.

Glenn Field is tense . . . quiet.

Suddenly, a deep rumbling of engines heralds the beginning of the launch of Zero X. Across the tarmac a huge, white hangar begins to move, sliding back to reveal the gleaming shape of Zero X. Hydraulic jacks hum and lift the craft clear of the apron ready for the next stage.

This is immediate. With the explosion of turbo–ramjets Lifting Body 1, followed by Lifting Body 2, moves towards the main body and clamps on like a colossal wing.

Then it is the turn of the Martian Excursion Vehicle, the flight deck. Once in line the M.E.V. separates from its housing tower, trundles to the front of Zero X before clamping into position.