past and future. Episodes 2 - 23 begin with the following narration (voiced by Dick Tufeld): Tony and Doug become participants in past events such as the sinking of the Titanic, the attack on Pearl Harbor, the eruption of Krakatoa, Custer's Last Stand, and the Battle of the Alamo, among others. General Kirk, Ray, and Ann in the control room are able to locate them in time and space, observe them, occasionally communicate with them through voice contact, and send help. When the series was abruptly cancelled in the summer of 1967 by ABC, they had not filmed an episode in which Tony and Doug are safely returned to the Time Tunnel complex. Possibility of time travel According to the plot, time travel is facilitated by time being portrayed as a static continuum, accessible at any point through the Time Tunnel as a corridor spanning its infinite reaches. When Senator Clark sees an image of the Titanic on the image screen in the course of episode one, he is told by Dr. Swain that he is seeing "the living past", and Althea Hall is told by Tony Newman that the past and the future are the same. The Time Tunnel is also a portal connecting the Time Tunnel "complex" with the same time periods in which Doug and Tony are located. Other people can also be relocated by the Time Tunnel from their time to another time as Machiavelli is switched from his own time to the time of the Gettysburg Campaign of 1863. Bringing people (other than Tony and Doug) to the present happens often in the series, but the only occasion in which Tony and Doug return to their own time occurs in "Merlin the Magician", when the great wizard uses magic to bring them home in suspended animation so he can instruct them to perform a mission for him. In the course of the series, Doug, Tony, and the Time Tunnel personnel discover that events of the past can be altered to some extent by the intrusion of the time travelers, and in a few cases, their historical research allows for it. Episode 26 ("Attack of the Barbarians") explores the scenario of one of the time travelers falling in love with someone from the past: Tony and the Princess Serit, daughter of Kublai Khan. Marco Polo tells Doug, "Can they not touch each other?" History itself hints