In 1970, they released their fourth album, "Deep Purple In Rock", the record that made them a true institution of hard rock. The simplicity of the riffs, combined with linear yet remarkably powerful melodies and enviable technique, propelled them to unimaginable heights, with millions of copies sold. The tranquil pop charts were shaken by the heavy metal of "Black Night", a true sonic cyclone that revolutionized the genre.
Deep Purple unleashes an arsenal of power, energy, and fury here, but with psychedelic and progressive contributions from Jon Lord's keyboards. The album is packed with classics like the harrowing "Speed King", the robust "Bloodsucker", and the progressive and virtuosic "Child in Time".
However, this resounding success foreshadows the first ego clashes among its members, all of them virtuoso instrumentalists and talented musicians. It's a struggle fueled by the difficult and clashing personalities of its members, especially Blackmore, a character as extremely elusive as he was difficult to manage, with an intractable temper.
Nevertheless, it would be he who provided the talent for the subsequent works that would follow in the next few years, some of which are considered true masterpieces of rock.

