R is for... Radnor

Commander Julian Radnor was a senior official on the T-Mat matter transportation project. He had previously been involved in rocketry, working alongside the pioneering scientist Professor Daniel Eldred. Earth turned its back on space exploration and concentrated entirely on the new T-Mat system to transport people and goods across the planet. Radnor had foreseen this and moved over to join the project, which caused a rift between him and Eldred.

When the moonbase which housed the vital T-Mat relay station was invaded by Ice Warriors, the system was brought to a halt - causing widespread chaos. In desperation, Radnor turned to his old friend, whom he knew to be working on a secret project to build a new rocket. This would be used to get a team to the Moon who would be able to solve the issues - which were thought to be purely technical at this point.

Initially resistant, the Doctor was able to help Radnor convince Eldred to co-operate. Too old to pilot the rocket himself, the Doctor and his companions volunteered to fly it.

Based in London's T-Mat Control, Radnor had to contend first with alien seed pods arriving, which could suffocate and kill when they germinated, and then with the appearance of an Ice Warrior - sent to ensure that the seeds could establish themselves on Earth and so change the climate to suit the Martian invaders.

Having more of a political role on the project, Radnor had an uneasy working relationship with the ambitious Gia Kelly, senior technician for T-Mat.

Played by Ronald Leigh-Hunt. Appearances: The Seeds of Death (1969).

• Leigh-Hunt would return to the series in 1975 to play another commander - Stevenson - in Revenge of the Cybermen.
• He had earlier played King Arthur in the TV series The Adventures of Sir Lancelot, which had starred William Russell in the title role - one which very much influenced his casting as Ian Chesterton.
• He would work again with Wendy Padbury in The Freewheelers, and can be seen in The Omen, which also featured Patrick Troughton.