In Search of... is an American television series that was broadcast weekly from 1976 to 1982. It was created after the success of three one-hour documentaries produced by creator Alan Landsburg. Rod Serling was the initial choice to host the spin-off show, but died before production started. Leonard Nimoy was then selected to be the host. The show was originally hosted by Nimoy. The original series was shown in Australia in the 1980s under the title Great Mysteries of the World.