George Harrison's resonant 12-string electric guitar leads "A Hard's Day's Night" were hugely influential; the movie helped persuade the Byrds, then folksingers, to plunge all out into rock & roll, and the Beatles would be hugely influential on the folk-rock explosion of 1965. The Beatles' success, too, had begun to open the US market for fellow English bands like the Rolling Stones, the Animals, and the Kinks, and inspired young American groups like the Beau Brummels, Lovin' Spoonful, and others to mount a challenge of their own with self-penned material that owed a great debt to Lennon–McCartney.