The government wants to shut down the Time Tunnel experiment. Thankfully they didn't or else we wouldn't have Lee Meriwether and her clipboard to look at.
Tony and Doug get lost in a time machine and its up to the supporting cast to try and lead them home through a series of time jumping adventures.
There are actually some pretty impressive set and effects in the first episode. after that they start to taper off and just become reused stock footage. Despite the historical inaccuracies and silliness its OK show to watch on a rainy day or late night