“On the Dark Side” is a song by American rock band John Cafferty & The Beaver Brown Band, though they were credited as Eddie & the Cruisers. The song was written and recorded for the 1983 film Eddie and the Cruisers about a New Jersey bar band, and appeared on the film’s soundtrack album. In the film, the song becomes the band’s big hit and leads to a second album and a conflict with their record company.

The movie Eddie and the Cruisers didn’t do very well when it was first released, and neither did this song. In an Interview, the music supervisor on Eddie and the Cruisers, Kenny Vance explains:

What happened was, the movie came out and that was the end of it. And about a year later, Cafferty and I were working on his second album. The big deal out of the whole thing was that Cafferty got a record deal. And so we were working on the second album and we got a phone call from Columbia that said, ‘You just sold 25,000 albums today.’ What are you talking about? They said, ‘Eddie and the Cruisers.’ When HBO first went on the air, they would play a movie for a month in rotation, like, you’d see it 7 times a day. And it became a f–king smash. And we were stunned. It just goes to show you, you show up, you do a great job to the best of your ability, and you never really know about the results. When the movie came out it bombed. We were very, very lucky with that, and wound up selling almost 4 million albums.

On October 20th 1984, John Cafferty & the Beaver Brown Band performed “On the Dark Side” on the ABC-TV program ‘American Bandstand’.

The song first entered the Billboard Hot Top 100 chart more than a year earlier on October 2nd, 1983 at position #64, though a 1984 re-release of the song helped it gain more fame. It re-entered in 1984 and the day after the band’s appearance on ‘Bandstand’, it peaked at #7 for 2 weeks and spent a grand total of 27 weeks on the Top 100. It peaked #19 on the Canadian Hot 100, and spent 5 weeks at #1 on the Mainstream Rock Tracks.

On the same ‘Bandstand’ show the sextet also performed “Tender Years”; it peaked at #31 for 1 week on January 6th, 1985.