Kirsten and the crew start in Salt Lake City, UT, and then head to the small desert town of Delta in search of Trilobites. These are extinct arthropods that flourished during the lower Paleozoic Era. Loy Crapo's Bug House is the site of their first encounter with the second most popular fossil group next to dinosaur fossils. Their next stop is U-DIG Fossils quarry, where they break open rocks to find a stash of prehistoric marine creatures.