The series began as a pilot ordered by NBC on January 15, 2020, directed by Thor Freudenthal and written by series creator David Appelbaum, before receiving a full 10-episode first season order on January 12, 2021.

The original 2020 pilot cast included Michael Raymond-James and Caleb Ruminer in the lead male and son roles, but they were replaced in March 2021 by Eoin Macken and Jack Martin, and the family's surname was changed to Harris.

Actresses Angel Parker, Catherine Dent, Jag Bal, and Rita Angel Taylor were originally cast in 2020 but do not appear in the final main or recurring cast lists, with Chloe De Los Santos replacing Taylor in April 2021.

For the third and final season, the cast agreed to be released from contracts that originally guaranteed payment for at least ten episodes per season, accepting a reduced six-episode order so they could pursue other work.

Filming took place in Melbourne and regional Victoria, Australia, starting May 3, 2021, and wrapping in September 2021, standing in for both present-day Los Angeles and prehistoric 10,000 BC.

The effects-heavy first season cost $71 million to produce in Australia, over $60 million of it spent in Victoria, making it the most expensive TV production in the state since Steven Spielberg's HBO series The Pacific wrapped in 2009.

The third season moved filming to Queensland, Australia, beginning around May 2023.

Rotten Tomatoes gave the series a 29% approval rating based on 21 critic reviews, with the consensus stating that the show 'doesn't commit to its insane premise hard enough,' while some critics like The Guardian's reviewer still enjoyed it for being 'gloriously, brazenly bad.'