<P> In the film, the song is performed by James "Jimmy" Mattingly II on lead vocals and guitar, Leonard "Lenny" Haise on lead guitar and backing vocals, "T.B. Player" on bass and backing vocals (as a running gag, the bass player in the film is unnamed), and Guy "Shades" Patterson on drums . For their live performance of the song on The Hollywood Television Showcase, studio bassist Scott "Wolfman" Pell replaced T.B. Player on bass and backing vocals . </P> <P> In the fictitious "mockumentary" liner notes from the soundtrack CD, "That Thing You Do" peaked at #2 on the Billboard Hot 100 during the summer of 1964 . </P> <P> The song was written by Adam Schlesinger, the bassist of the alternative rock group Fountains of Wayne . Schlesinger did not expect his song to be chosen, but tried as "a personal exercise". Performers include Mike Viola on vocals with Schlesinger on backup vocals . </P> <P> The song was released as a single, and although not as successful as was depicted in the film, the track still did moderately well in the US, peaking at #41 on the Billboard Hot 100 . (It also reached #22 on the Adult Contemporary chart, #18 on the Adult Top 40, and #24 on the Top 40 Mainstream chart .) </P>

Who actually sang the song that thing you do