Tommy James + The Shondell’s “Crimson and Clover” had an unexpectedly quick release in 1968 after it was leaked by a radio station. The track went to #1 in the US, Canada, New Zealand, Switzerland, and South Africa. Pitchfork named it the 57th best song of the 1960s.
According to Wikipedia, the tune has been covered by many artists, including Joan Jett and Prince. However, the tune’s cultural impact goes far beyond cover versions: it’s mentioned in the movie Less than Zero and dozens of other films and TV shows. Its distinctive title has been dropped into lyrics by artists and bands including The Dandy Warhols, Bob Dylan, Jimmy Eat World, Kings of Leon, Elliott Smith, Liz Phair, Green Day, and Lana Del Rey.
As the tune builds in intensity near its end, the modulation hits (4:19) and the extreme tremolo used by the guitars throughout the tune spreads to the vocals. Many thanks to expert mod stringer JB for this contribution.