The annual midwinter hike is no walk in the park for the students of Azumano Middle School. Daisuke has been dreading the trek all year, but at least he gets to show off his rugged charms for his beloved Risa. But when Daisuke and Riku find themselves lost and alone on the frigid mountainside, it's Dark to the rescue. Can the Phantom Thief save the day without blowing Daisuke's cover?