A ghola is a fictional creature in the Dune universe created by Frank Herbert. Similar to clones, they are "manufactured" human duplicates grown in an axlotl tank from cells collected from a deceased subject. A true ghola is initially shown to be the 'resurrection' of a corpse, through regrowth of damaged tissues, while later gholas in the series are more accurately described as clones - grown from genetic material extracted from a few cells (e.g. a small scraping of skin taken moments before death). Through specific stresses, gholas can be made to recall the memories of the original, including their moment of death. In Herbert's Dune series, the technological process is developed and initially monopolized by the Tleilaxu; in later novels the process is also used by the Bene Gesserit.
The first ghola featured in the series — Hayt in 1969's Dune Messiah — is a resurrection of the corpse of Duncan Idaho. Later gholas are grown from a few cells, as in the case of subsequent Idaho gholas provided to Leto II, as described in God Emperor of Dune (1981). The Tleilaxu can control their creations by forcing them into a hypnotic state with some predefined sound (often a specific humming or whistling noise) that has been pre-conditioned into each ghola.
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