In Deep Purple lead singer Ian Gillan's autobiography, he explained that this song began as a joke: someone mentioned the classical composition "Flight of the Bumble Bee" and their organ man, Jon Lord, started playing variations around it.
"The Rat" is a reference to a drug habit - Deep Purple made occasional anti-drug references in their songs - "Into The Fire" was another.
Suggestion credit: Dougie - Delhi, India, for above 2
In Rock was the first album with the Mark II lineup of Deep Purple, which introduced bass player Roger Glover and lead singer Ian Gillan. This is the lineup the band returned with in 1984 after an eight-year hiatus.
John Lennon's lead guitar work on Yoko Ono's "Walking On Thin Ice" proved to be his final creative act. It was upon their return home after completing laying down the track that Lennon was murdered by Mark David Chapman.