Using their time viewer, three scientists see a desolate landscape 107 years in the future, at which point the electrician realizes that the viewer has unexpectedly become a portal. All four jump through, only to have the portal collapse behind them, whereupon they are chased on the surface by Morlockish creatures who are afraid of thrown rocks, and they meet an advanced, post-apocalyptic, underground society that employs androids and is planning a generation-long trip to Alpha Centauri.

The film draws in at least four important additional time travel tropes: suspended animation, a single nonbranching, static timeline (with the corresponding inability to go back and change it), experiencing the passage of time at different rates, and a trip to the far future. And according to the SF Encyclopedia, the film was originally conceived as a sequel to the 1960 film of The Time Machine.

The writer, David L. Hewitt, took chunks of plot and script from The Time Travelers (1964), swapped the blonde for a brunette, swapped the accidental time gate for an accidental time rift that drags the whole lab through time as if it were a time ship, added a anachronistic dinosaur, and ended up with an unwatchable movie.

Like the 1964 version, this version has a brief mention that it’s impossible to change events that have already happened, but unlike the original, the montage at the end of the film is mere chaos that no longer reinforces the idea of a single deterministic, nonbranching timeline. Despite that, I enjoyed the consequences of the villainous character running into himself, but at the same time, I dismayed at the discussion of how meeting yourself could instantly cause a disastrous explosion or implosion or maybe something-or-other (the audio was unintelligible at 1:12) would cease to exist. (I pray that the space-time continuum wasn’t in peril).