The live action scenes and a majority of the stop motion effects were all filmed in 1994, but David Allen, the director, had passed away due to cancer in 1999. The studio that was making this movie, Full Moon Studios, was also having financial issues so they had to keep postponing the production of the movie, until they ran out of money and had to shelf it. In 2019, after an online fundraising campaign, the original effects artist, Chris Endicott, returned to complete the remaining stop motion sequences.
The stop motion animation models of the lizard men were kept by many of the effects artists over the years, including Chris Endicott.
Once it was finally completed, producer Charles Band initially planned to issue the film straight-to-streaming, but he decided it needed to be viewed on the big screen, so it began appearing at film festivals in the summer of 2023.
The movie evolved from the short presentation film Raiders of the Stone Ring (1968) by David Allen. He encountered various issues getting a feature length version produced and decided to revise the plot when it was announced that Disney was making Insel am Ende der Welt (1974), which featured a similar story. In 1975, Allen collaborated with fellow FX-man Randall William Cook on the first draft of the script for "The Primevals," and when Cook wrangled him a job as an animator on Laserkill - Todesstrahlen aus dem All (1978), Allen went to work revising his short to screen it as a pitch for producer Charles Band. Band liked it and agreed to produce the film, which was first slated for a 1980 release and publicly announced with a lavish 18-page article in the Winter 1978 issue of Cinefantastique. Unfortunately, it was cost-prohibitive and remained on Band's slate of forthcoming pictures throughout the 1980s and 1990s, but it wasn't until 1994 when he found himself in a financial position to shoot it. Allotting two years for the stop-motion animation to be completed, it was supposed to have been released in 1996, but Band lost his distribution deal with Paramount, Allen became sick and died, and the movie was shelved. In 2018, Band raised $40,000 through an Indiegogo campaign to finish the film, which was finally completed in late 2022.
5% of the original camera negatives were lost. A 35mm workprint included the missing footage, but there were scratches and other anomalies, so these segments had to undergo painstaking restoration to match the quality of the rest of the film.