He said: “I can tell you exactly. Freddie wrote the lyric, and he already had a riff that he had played with his old band. I said, ‘That’s a great lyric and concept, but you need a better riff.’
“Freddie said, ‘OK, what do you got?’ I started doing this frenetic riff to match the lyrics, and he really liked it. The whole band got into it, particularly Roger [Taylor, drums], because it’s very much based on the way he plays. It clicked quite quickly.
“For some reason, we didn’t put it on the first album. We liked it, but we stuck it in a drawer thinking it would go on the second album. But that record was very highly arranged because we were consciously trying to push our music into a new place.
“Some people were pleased, but others weren’t. I remember getting a review in Australia saying, ‘QUEEN have abandoned their rock roots on Queen II. I was shocked.
“But that kind of response was an influence on Sheer Heart Attack, which was a deliberate attempt to recapture our original energy. We laid down “Stone Cold Crazy” very quickly, and we played it quickly. It’s one of the fastest tempos we’ve ever played.
“These days, if we play it on stage, we have fun with it. Sometimes we try to prove to ourselves that we can still flex our muscles at that rate, so it tends to get very fast. That’s when you have to pull it back because it gets to the point where it loses its thump.”