[2] Produced by Adam Schlesinger, the album's power-pop sound was a departure from the darker, textured sonics of The Verve Pipe and Villains.

The song "Colorful" appears in a 2001 movie Rock Star in which lead singer Brian Vander Ark provided a singing voice for Mark Wahlberg's title character performing this song and portrayed as Ricki Bell, a bassist for a fictional heavy metal band Blood Pollution.

Billboard praised the album's turn to "power-pop territory," and wrote that singer Brian Vander Ark "has never sounded more like Peter Gabriel, and we mean that in a good way.

"[7] The South Bend Tribune wrote that "Vander Ark writes five of the songs on Underneath, and drummer Donny Brown writes four of them, and the differences between them help to make Underneath a constantly shifting tilt of emotions and, probably, a much better album than if just one of them had been the main songwriter.

"[8] The Detroit Free Press called the album "the best stuff the group has concocted in half a decade.