Tom Waits' 'What's He Building' stands as a gritty, atmospheric centerpiece on the 1999 album Mule Variations. The track exemplifies Waits' signature blend of bluesy instrumentation and noir-tinged vocals, capturing the weary spirit of a working-class protagonist navigating the American South. With its driving rhythm and cryptic narrative, the song reinforces the album's exploration of urban decay and the lives of marginalized figures. As part of Waits' extensive discography, the recording maintains the raw, unpolished aesthetic that has defined his career since the late 1970s, offering a haunting glimpse into the musician's continued evolution as a storyteller through sound.