The frontman says they only realized what they'd achieved after guitarist Mike Campbell observed: "You sing like you did on the first two albums." Petty tells Rolling Stone: "I knew I wanted to do a rock'n'roll record. We hadn't made a straight hard rocking record, from beginning to end, in a long time."

It's taken nearly three years to get there, but he explains: "You must get the songs. It takes time to write 10 or 11 really good songs." And it wasn't plain sailing - when he first played his track American Dream Plan B with his bandmates, the response was complete silence.