Returning from a fishing trip to find food for her chick, the female chinstraps' first challenge is getting ashore. They must make it onto the steep beach with its crashing waves and powerful undertow. Once safely landed, there's still a long journey on foot in store for these flightless birds. They have chosen to raise their chicks on the rim of a volcanic crater so have a gruelling climb over glaciers covered with muddy volcanic ash. It's like a game of snakes and ladders as each triumph is set back with a slippery slide back down. Using a combination of beak, wingtip and feet gets them through. Once at the top, they join penguin rush hour along the level ground. Each must find its own family in the mass of 150,000 other penguins, using only her acute sense of hearing to pick out the cry of her own baby.