Two young couples are driving through a remote forest when their car breaks down. When a run-in with a curious grizzly bear ends up with the bear being shot to death, the bears mate arrives on the scene and vengefully attacks their van. The couples are trapped inside the disabled car and must come up with clever ways to survive. As they battle the surprisingly intelligent creature, and contemplate their uncertain fate, secrets begin to emerge that threaten to tear the group apart before the bear does.

In the first episode Dr Alice Roberts looks at how our skeleton reveals our incredible evolutionary journey.
Trekking through the forests of our ancient ancestors, she goes to meet the apes who still live there today - chimpanzees. In six million years we have become very different, and what kick-started this can be found in an extraordinary fossil - Sahelanthropus. A single hole where the spine was attached suggests that our ancestors started the journey to being human by standing upright. We take it for granted, but standing up and walking is surprisingly complex - each step involves the co-ordination of over 200 muscles.

In the first episode Dr Alice Roberts looks at how our skeleton reveals our incredible evolutionary journey.
Trekking through the forests of our ancient ancestors, she goes to meet the apes who still live there today - chimpanzees. In six million years we have become very different, and what kick-started this can be found in an extraordinary fossil - Sahelanthropus. A single hole where the spine was attached suggests that our ancestors started the journey to being human by standing upright. We take it for granted, but standing up and walking is surprisingly complex - each step involves the co-ordination of over 200 muscles.