Utilizing the talents of numerous friends and collaborators (including Mötley Crüe percussionist Tommy Lee), McMahon began work on the collective's debut following Something Corporate's hiatus in 2004. The resulting Everything in Transit, a sunny pop/rock "concept album exploring his alienating return to the hometown he left to pursue his music," was released on Maverick Records in August 2005 to a positive critical response. Fans also approved of McMahon's new sound, and Everything in Transit debuted at number 37 on the Billboard album charts. However, a supporting summer tour was canceled after McMahon was diagnosed with Acute Lymphatic Leukemia that same summer. He underwent a successful bone marrow transplant from his sister (for whom Something Corporate briefly reunited to record the song "Katie") and embarked on the long road to recovery.

As McMahon recovered, a video for the album's first single, "The Mixed Tape," began making waves on VH1 and MTV. Jack's Mannequin played sporadic shows in 2006, headlining a brief summer tour before serving as the opening act for O.A.R. on nation-wide dates. A repackaged version of Transit appeared that fall coupled with a bonus DVD, and the band returned to the studio in mid-2007 to begin work on a sophomore effort. McMahon graced the cover of Alternative Press in January 2008, while an article inside the music magazine hyped the upcoming Jack's Mannequin release as one of the most highly anticipated albums of 2008. Although originally scheduled for a summer release date, The Glass Passenger ultimately arrived that September. People and Things, the group's third studio album, was released on October 4, 2011. The first single, “My Racing Thoughts,” debuted earlier in the year. ~ James Christopher Monger & Andrew Leahey