He quickly became obsessed with his creations, considering them to be the ultimate form of life superior to all others, and in order to safeguard their existence he arranged for his own people to be wiped out by the Thals to stop them from closing down his Dalek project. The Daleks then exterminated the Thal victors.
Davros first appeared in Genesis of the Daleks, where he was played by Michael Wisher, whose performance in the role is acclaimed by many fans. It has been said that almost everything said by Davros in this story is quotable, with a discussion between himself and the Fourth Doctor (Tom Baker) on the topic of the creation of a hypothetical lethal virus being an example. At the end of this story, he is killed by his own creations, the newly-created Daleks, when they turn their guns on him.
He proved too effective a character to be kept dead, however, and he was resurrected seven years later in Destiny of the Daleks, on the grounds that some kind of self-repair mechanism built into his life-support chair had saved him and then very slowly (over a period of centuries) restored him. Further repeat appearances followed in Resurrection of the Daleks and Revelation of the Daleks. Many consider these to be a good example of the law of diminishing returns. This is particularly in regard to the increasingly implausible mechanisms by which Davros' almost universally sticky fate at the end of the previous story is explained away.
His last appearance was in Remembrance of the Daleks by Ben Aaronovitch, physically reduced to a head in a customised Dalek casing. In this story, set in London in 1963 and regarded as one of the best Doctor Who stories to emerge for quite some time, both he and Skaro were apparently destroyed by the Seventh Doctor.