Lost Worlds with Monty Halls and Leo Houlding

Within Guyana's western highlands hides Oshi and Kamarang, waterfalls three times higher than Niagara falls; Monty and Leo lead a seven day expedition to this lost world.

Monty Hall and Leo Houlding aim for the highest possible point, and the remotest possible part, of the Guyanan rainforest to explore new wildlife and terrain.

Deep in the Borneo rainforest, Monty and Leo attempt to scale a 300 meter cliff in the Melinau Gorge to survey its unexplored wildlife.

Beneath Borneo's rainforest lies one of the world's largest cave networks; Monty and Leo hope to uncover more than the 300 km of tunnels so far surveyed.