Krypto and Streaky (problem which I'll talk about later) are out on patrol one day when they come across a caterpillar and save him from the huge gusts. Streaky, however, is much more concerned about food (he's like that a lot in later episodes). Anyways, switching scenes, we see Lex Luthor for the first time in the show, and we're also introduced to his pet lizard, Ignatius, who's self-centered, lazy, and can hardly even catch his dinner. After witnessing the results of a growth ray, the scientists walk off with Lex into another room, leaving Ignatius to toy with the ray. And, of course, the caterpillar has something to do with this episode, so naturally he decides to unleash the growth ray on him, making him larger. However, due to a defect in the machine, the target keeps growing periodically to a certain extent, leaving Ignatius with a bit more than he can chew. As the problem grows, Krypto shows up and tries to stop the bug before he gets into anymore trouble. However, a detour into a pillar of a train track makes him repair the structure, giving Ignatius enough time to trap the caterpillar. In the end, the greedy lizard doesn't get his way when he discovers a cocoon in place of his meal.
Two problems here. Streaky (Supercat) is introduced here in this episode (technically), when his real intro is later. And, a much smaller issue, Ignatius seemed to already know about Superdog even though we weren't introduced to him in another episode. This is only a small flaw, however, so it's not something to care too much about. I felt like this episode was pretty good and is what the series is really about. 9.6/10