The DeBoors Diamond Mines Ltd. and the Panther Diamond Mines Ltd. are right near each other. Guess which one is the big company and whose has a shack for a building? At least the PP has a tunnel directly underneath his shack, and we see him walking through it and carrying out a huge diamond and putting it in his huge vault.
Soon we discover the men next door are digging underground and stealing the Panther's diamonds. Our hero thinks it is gophers, and goes next door to ask his rivals if they have seen any gophers. They reply by shooting him!!
By the way, this is another PP episode in which we get dialog which usually means a poor cartoon, but it's fine here. It's still odd to hear the PP's voice, although it's done by famous voice-impersonator and star of American TV in this era: Rich Little.
The funniest thing in this cartoon might be Little's impression of Alfred Hitchock! He gives one of the villains, "Devereaux," Sir Alfred's voice. It's very good, and I'm surprised no one, including IMDb, has commented on that.
Overall, the humor was on the light side. Looney Tunes does a much better job at this sort of thing. However, since it was only one of two cartoons in which the Panther talked, it's worth having in your collection - and the Hitchcock imitation is priceless!