Twistor quadrics and black holes

A simple procedure is given to construct curved, non-self-dual (complexified) Kaehler metrics on space-time in terms of deformations of holomorphic quadric surfaces in flat twistor space. Imposing Lorentzian reality conditions, the Schwarzschild, Kerr, and Plebanski-Demianski space-times (among others) are derived as examples of the construction.