First coming together at the dawn of the British Invasion, hard-rock heroes Status Quo finally shot to international success in 1968. They started out playing catchy psychedelic pop that was loaded with wild, fuzzy guitar, but the band really hit their hard-driving groove in the early '70s, perfecting the bluesy style known as boogie rock. Despite constant lineup changes, guitarists Francis Rossi and Rick Parfitt have remained the band's musical foundation since the '60s, and they've continued pounding out heavy anthems decades after most of their peers hung up their boogie shoes.