The main conflict centers on the villain Lizard Lips, who poses as an ordinary scientist and creates a time machine to summon a Tyrannosaurus dinosaur to serve as his mount in his plan to take over the world. The Super Duper Bunny League must stop him and his dinosaur from causing chaos at Important City, including disrupting a baseball game where Stumpy is practicing to throw the first pitch.

Key characters include Lizard Lips, the villain who uses a time machine to summon a T-Rex; Stumpy, who is practicing throwing out the first pitch at the Important City baseball game; Bex, who helps Stumpy; and other members of the Super Duper Bunny League such as Handsome Steve and Middy. Derek's birthday is also a subplot in the episode.

The Tyrannosaurus is summoned by Lizard Lips using a time machine and serves as his mount. The dinosaur causes trouble at Important City, including threatening fans at the Important City ballpark, and is a major obstacle the Super Duper Bunny League must overcome.

The episode takes place in Important City, where the Super Duper Bunny League operates. Important City is the location of the baseball game where Stumpy is practicing the first pitch, and it is also the site of the chaos caused by Lizard Lips and his dinosaur. The city is frequently threatened by various villains, and the League defends it from these dangers.

Notable scenes include Stumpy practicing the ceremonial first pitch with Bex's help, Lizard Lips posing as a scientist at Important City Laboratories, the summoning of the T-Rex, and the dinosaur causing havoc at the Important City ballpark. Additionally, there is a subplot involving Derek's birthday and a cupcake run interrupted by space pirates, linking to the episode's dual title 'Lizard Lips / Space Pirates'.