If you're lost in the African Savannah, you will need to follow a stream back to its source rather than down stream where it eventually will just disappear.
Bear Grylls is in Mexico, and finds a cave that has been used by the Rarmuri people. There are signs of humans and he even finds a useful piece of wire.
In this Web exclusive video, an uncharacteristically dispirited Bear Grylls fights his way through a dangerous combination of thick cloud, torrential rain and dense vegetation.
Duncan Gaudin (first assistant director), Rob Llewelyn (director of photography) and soundman Colin Bowes take you behind Bear Grylls' vine climb in the Dominican Republic.
Making it down a cliff in the Copper Canyon can be very dangerous, and Bear Grylls is very happy to see some traces of Coyotes, since that must mean there's a way down.
Bear Grylls will have to jump in one of the Canyon rivers to make his way back to safety, and in order to make sure the jump is safe, he first makes a depth gauge to measure the depth of the water.
Bear Grylls gets dropped at the top of the Copper Canyon, and the view is spectacular. The landscape is almost untouched and will pose a massive challenge for anyone stuck there.
Bear Grylls shows us a trick to figure out how much daylight there's left before the sun goes down in the Canyons. He also finds a scorpion to snack on.