The dream of sending humans to Mars is closer than ever before. In fact, many scientists think that the first person to set foot on the Red Planet is alive today. But where should the first explorers visit when they get there?
Horizon has gathered the world's leading experts on Mars and asked them: where would they go, if they got the chance - and what would they need to surviv...
Follows the Mackenzie Shirilla case, a 17-year-old who intentionally crashed her car into a brick wall in Ohio, killing her boyfriend Dominic Russo and his friend Davion Flanagan. She was convicted of 12 felonies.
An unflinching portrait of Dean Potter, the influential and controversial climber, base jumper and highline walker, who achieves jaw-dropping feats while battling his inner demons.