The Bushmen's plan to connect old underground drives calls for a huge drill. Slim Pickings face disaster when their rickety tractor breaks down.

The Kilchers tackle some major jobs. The men reclaim lumber for Shane's cabin, Eve makes a gruesome discovery and Atz Lee and Jane find signs of an aggressive bear.

Josh joins a daring experiment to replicate the ancient pyramid build. First-of-their-kind 3D scans reveal an undiscovered void beneath the stone.