IRON MAIDEN - Seventh Son Of A Seventh Son LP

Highly recommended. 

Seventh studio album by the English heavy metal band, released 1988. 

It is the first Iron Maiden release to feature keyboards. Like The Number of the Beast and, later, Fear of the Dark, The Final Frontier and The Book of Souls, it debuted at No. 1 in the UK Albums Chart. It also marks the first appearance of many progressive rock elements which would be used frequently in later albums, seen in the length and odd time signatures of the title track "Seventh Son of a Seventh Son", and by the fact that it is a concept album.