The second part of the landmark series about the wildlife of the Scottish Highlands narrated by Ewan McGregor. Summer is the most intense of all the seasons in the Highlands. Animals are in a great race to raise their young to independence before the nights close in and the storms of autumn arrive. Some, like otters and pine martens, are single mothers working ceaselessly for their young, while others, including golden eagles, work in pairs to look after the chicks. Most spectacularly of all, young guillemots on dramatic Handa face a leap for life as they tumble to the sea from 400ft cliffs.

• Ewan McGregor