Puharich was impressed by the stories about the Dutch psychic Peter Hurkos and invited him to the U.S. in 1956 to investigate his alleged abilities (see below). In 1960, Puharich investigated materialization séances at Camp Chesterfield, but discovered the use of cheesecloth being used to fake ectoplasm. Puharich played himself on "Perry Mason" television series, in the episode, "The Case of the Meddling Medium," in 1961. He conducted a series of three tests to help determine the ESP of Mason's client accused of murder. During the third test, the actual murderer was exposed.