Beppe Grillo, co-founder of the Five Star Movement (M5S), is today expected to return to his native Genoa after sweeping into Rome to seize back control of Italy’s biggest opposition group. Two years ago the former comedian had handed the reins to a five-strong “directorate”. But last month he announced: “I’m back.” He has since met the M5S’s lawmakers in the capital. In recent months his movement has been plagued by setbacks. The latest came this week when Federico Pizzarotti, who gave the M5S its first electoral breakthrough to become mayor of Parma in 2012, resigned his membership. In June the M5S took Rome. But its mayor, Virginia Raggi, has struggled to form an executive amid mishap and controversy. The polling gap between the M5S and the governing Democratic Party has widened. That helps the prime minister, Matteo Renzi, as he strives to win a constitutional referendum in December on which he has staked his premiership.