While performing his duties on the ranch, Hank the Cowdog finds that his bones are disappearing, and his friend Drover claims to have seen a monster do it.

Happy the Lab is back on the ranch, and it looks like he's up to his usual good-natured, bumbling ways! And, it just so happens that he has wandered onto Hank's ranch on a particularly exciting day: rain has finally come to their drought-stricken land, and--what's even more exciting--radio reports claim that there's a mountain lion on the prowl in their area! As the day unfolds, it appears that the mountain lion report was bogus, which is a good thing,...