can someone summarize a&o 4?

I Don't exactly know every detail, but I think the pups are told a story or something, and they find this cave that is apparently haunted that has sacred treasure or something. I could be wrong, not saying that is confirmed. It's what I took in and identified what the trailer showed me.

if you want to see it, link

Click on play for watch the movie

Lilly takes the omega school on a field trip to Sawtooth Cave in a forrest. Runt and others find out its haunted. Runt comes back later and sees a wolf in the cave. Even later he comes back to talk to her <backstory> . So they go to Rabbit Poo Mountian. And other details