"Hero and Heroine" is a song by English band Strawbs featured on their 1974 album of the same name. It is written by Dave Cousins and has obvious drug allusions, the main reason it didn't get much airplay on BBC radio. The song is in a similar vein to an earlier track "Witchwood" but with rather more obvious allegory.
Dave Cousins originally demonstrated the song to the band on banjo and the guitar picking under the verses does indeed retain a bluegrass feel. Keyboardist John Hawken and guitarist Dave Lambert added mellotron and guitar power chords between the verses which gives the whole song a more epic bearing.
The B-side track "Why" is another Dave Cousins composition, not released on any studio album. It forms the first part of the composite song "Why and Wherefore" which appears on the compilation/rarities album Halcyon Days.