Lord Fear was the leader of the opposition team of characters in the kid's TV series Knightmare from series five (1991) until the last series, series eight (1994).
Played by Mark Knight, (who also played other Knightmare characters Sir Hugh De Witless, Ah Wok and Rothberry) Lord Fear resided in his chamber in Knightmare Castle from where he would command his minions (such as Lissard, Scarkill and Sylvester Hands) and hold another member of the 'Good Team', the Powers that Be. (Most often the neutral warlock, Hordriss or the good wizard, Merlin.) Lord Fear would communicate with his minions via a magic pool, which looked uncannily like a bird bath.
Lord Fear's greatest weakness was that his chamber was bugged, allowing dungeoneers to use the spyglass item that could be found in some quiz rooms to see what Lord Fear was up to at that moment. (the scenes however were pre-recorded) Lord Fear did have an anti-surveillance strategy however, and after a minute or so of the dungeoneer's spying, Lord Fear would be alerted that he was being spied upon and either a fireball would be launched (presumably this could travel through the spyglass and kill the dungeoneer, although this never actually happened) or Lord Fear would look directly at the camera. (indicating he knew where you were and would send his minions to you post-haste)
Lord Fear's introduction to Knightmare co-coincided with his arch-nemesis Treguard's "softening up", which was generally seen as a bad thing by die-hard Treguard fans. Lord Fear and his co-horts did add an extra depth to Knightmare at a time when it was probably starting to lose some of its innovation and ingenuity through its more conventional means. Even though the part of Lord Fear was played brilliantly by Mark Knight, I don't think the outright evil he was supposed to portray made for as great a villain as Treguard did with his black humour and witty one-liners.
Interesting fact: Lord Fear's magic communication pool was always empty, even when in use. Mark Knight used to just talk into it and the producers would add whoever's face he was supposed to be conversing with afterward.