309. Space Sentinels 09: Voyage to the Inner World

In which X7 sees the young Space Sentinels take a journey to the center of the Earth's core (not really, but they do go underground) in the ninth episode. It is a good, if slightly predictable episode of the series. It does feature a Thagomizer, which is cool. Too bad it was the late 70s and we don't get to see it in use. It is a good episode though, and keeps things interesting until the end. Sink, Sentinels, sink!