A bulbous-headed brown bird with a comically large bill. Brownish overall, with a rich chestnut cap and paler underparts. Face is liberally splattered with black splotches, the largest patch on the ear where it forms a thick crescent. Pale yellow bill is oddly twisted, making it seem as if the bird is smiling. Prefers brushy habitats with dense cover, including bamboo stands and heavily overgrown field edges, in foothills up to montane areas. Joins mixed flocks. Can be difficult to see in thick cover, but will perch up to sing. Song a repetitive “aw-wi-WI-WI-Wi-WI” whose pitch and cadence may vary.