Land of the Lost is a 1974–1976 TV series relating the adventures of the Marshall family (including Will and Holly and their father, later replaced by their uncle). The Marshalls become trapped in a pocket universe populated by dinosaurs, ape-like creatures called Pakuni, and anthropomorphic reptilian creatures named Sleestak. This article concerns these characters, along with other human and alien visitors to the Land of the Lost. Travel to the Land of the Lost is almost always accidental, via "time doorways" that appear to glow and/or billow mist. These doorways sometimes appear to open and close spontaneously, but they can also be opened and controlled by Pylon crystal matrix tables and by a matrix table in the Lost City. Time doorways obey a form of temporal energy conservation law: whenever something enters the Land of the Lost via a time doorway, something else must then leave it, though not necessarily at exactly the same time. This aspect was abandoned in the show's third and final season, after new producers took over and the show's mythology was substantially changed. At least one Pylon periodically travels to other universes, acting as a sort of "interdimensional elevator", triggered by a conjunction of the Land's moons that occurs every three to four years. One of the universes it stops at along the way appears to be the Marshalls' home Earth. Humans The Marshalls Rick, Will, and Holly Marshall are the initial human protagonists on Land of the Lost. Rick is later replaced by Uncle Jack. Rick Marshall, his son Will, and his young daughter Holly were rafting on the Colorado River in the Grand Canyon when they were caught in "the greatest earthquake ever known". The river was diverted over a cliff, and as the Marshalls' raft plunged over the resulting waterfall they struck a time doorway partway down. Trapped in the Land of the Lost with only the minimal camping equipment they'd had on the raft, they make their camp in a natural cave partway up the face of a cliff they call the High Bluff. The three of them are from California, though Rick grew up on Ford Street in Indianapolis and attended Fillmore High there. The Marshalls formerly lived in Harrisville, Indiana. Mrs. Marshall died of unspecified causes when Will and Holly were very young, and neither of them remembers her very clearly. Rick describes her as being headstrong and beautiful,