The idyllic first theme in F major (a key often used to depict pastoral scenes) contrasts with a fiery middle section, no longer in F major, but in the gloomy F minor. The opening section returns at the end – after the ‘tempest’ has passed – unaltered, which is unusual in Chopin's music. The double notes in the middle section certainly form the most challenging moment in the piece and require light and well-controlled fingers to maintain the speed without accumulating tension.