Timewyrm: Genesys is an original Doctor Who novel, published by Virgin Publishing in their New Adventures range of Doctor Who novels. It was the first book in that series (and the first book in the Timewyrm quartet), and was thought of by some fans as a continuation of the television series; in effect, a Season 27 to follow the televised Season 26. The novel featured the Seventh Doctor and Ace; it also features a brief cameo of the Fourth Doctor – in the form of a holographic message to his future self – and the Seventh Doctor briefly uses the TARDIS to summon the personality of his third incarnation when he needs his past self's technical expertise. The book makes extensive use of characters and plot elements from the Mesopotamian myth of Gilgamesh. Source: Wikipedia (en)