A bit of heavy metal to round off your Friday as we acknowledge 37 years since the release of arguably Iron Maiden's most iconic album: The Number of the Beast, released through EMI and Harvest Records. There's a good reason why this project will always be a timeless classic.

The record was the band's third studio album, and the first to feature their legendary frontman Bruce Dickinson. It came the following year after Killers, and was the last album before the departure of drummer Clive Burr. The Number of the Beast was Iron Maiden's first album to top the UK album charts and featured the single Run to the Hills which became their most popular song at that point.

Iron Maiden - The Number of the BeastIron Maiden - The Number of the Beast

Naturally, the album had its controversies. It didn't get the warmest reception in the US thanks to its dark, Satanic imagery in the album title, art and lyrics of the titular single. There were even protests during their Beast on the Road tour where people publically burned the band's albums. Needless to say, it only served to publicise them further.

Perhaps people had a good reason to be nervous; there were apparently some rather spooky reports of unexplained phenomena during the album's recording sessions in London. From lights turning on and off on their own to some of the equipment stopping working with no explanation, those involved were plagued by issues. But things came to a head when producer Martin Birch (Fleetwood Mac, Deep Purple, Black Sabbath) was allegedly involved in a car crash with a mini-bus full of nuns and was later billed £666 for repairs.

It's amusing to think how often millenials get labelled as over-sensitive when back in the 80s, people were so frightened of Iron Maiden's skeletal mascot Eddie that he was edited out of The Number of the Beast music video on MTV. 

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Whether you enjoy the dark aesthetic of this record or not, it's safe to say The Number of the Beast is one of the all-time most important heavy metal albums to have ever been released.