The Hand of Fear is the second serial of the 14th season of the British science fiction television series Doctor Who, which was first broadcast in four weekly parts from 2 October to 23 October 1976. The serial was the last regular appearance of Elisabeth Sladen in the role of Sarah Jane Smith in Doctor Who.

Millennia ago on the planet Kastria, a traitor and criminal named Eldrad is sentenced to death for his crimes, including the destruction of the barriers that have kept the solar winds at bay. The pod containing the criminal is obliterated—but his hand survives. In the present day the Fourth Doctor and Sarah Jane Smith arrive in the TARDIS in a quarry and are caught up in a quarrying explosion. Sarah Jane is rendered unconscious but in that state makes contact with the fossilised hand, its ring placing her under its control. The Doctor takes her to the local hospital, where the mesmeric power of the hand becomes more complete and both Sarah Jane and a pathologist called Dr Carter are brought under its control.

Sarah Jane heads for the nearest nuclear generator, the Nunton Complex, where she causes a crisis by breaking into the reactor with the hand. It seems to thrive on radiation and begins to regenerate, growing back its missing finger and moving around unaided. The head of the complex, Professor Watson, remains at his post when the reactor goes critical. He offers the Doctor aid and advice in trying to get to Sarah Jane despite Carter attempting to stop the Doctor before falling to his death. Eventually the Doctor is able to reach Sarah Jane and knocks her down, but not before the hand has absorbed a significant amount of radiation. Retreating, the Doctor takes his companion to the medical center.

The hand's ring next takes over a nuclear operative called Driscoll, who is manipulated into bringing the hand into the reactor core while everyone else flees the complex. An RAF bombing raid simply adds to the available radiation and allows Eldrad to regenerate into a fully humanoid form. Finding herself in a female form, she uses her powers to learn from the Doctor why the humans have attempted to destroy her. Eldrad convinces him to take her back to Kastria, explaining that she created the solar barriers that enable her people to thrive, claiming that they were subsequently destroyed when Kastria was caught in the middle of an interstellar war.

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