Led Zeppelin's second long player was recorded in a relatively short amount of time. It was tracked, mixed and produced in different studios during breaks between the band's 1969 European/American tour. From start to finish it captures the developing energy, confidence and prowess of a young, phenomenal hard rock band on the rise. "Thank You" is so beautiful and romantic, that proto head-bangers like "Whole Lotta Love" with its mind melting, psychedelic breakdown almost seem out of place. II also furthered the band's epic, electric, bastardization of the blues while drawing the blueprints of metal.