A dark, medium-sized songbird with a long orange-sided tail, totally unlike any other redstart. Breeds in shrubby montane areas, particularly in the transition zone between forest and more open habitats; winters in similarly dense habitat at lower elevations. Male is predominantly grayish blue, with orange tail edges and a white belly. Female lacks the namesake white underparts and is instead brown overall with darker upperparts. Immature males have a blue head and chest, but are otherwise brown overall. Other redstarts in its range have a noticeably shorter-tailed profile. Song is an alternating series of clear, bell-like whistles and slurred whistles; most common call is a hard “tuktuk,” like stones knocking together.