Mario Balotelli has a reputation like no other in football. Since exploding on to the scene at Inter Milan in 2007, he has won league titles in both Italy and England, moving between Europe's elite clubs. Yet for all his undoubted talent, he is better known for his off-field antics – not least his infamous run-ins with both the police and Manchester's firefighters. Once described by José Mourinho as 'unmanageable', match-winning performances at the highest level have continued to convince clubs such as AC Milan and Liverpool to give him a chance. With exclusive access to friends, teammates and coaches, acclaimed football biographer Luca Caioli talks to the people best placed to explain the mystery that is Mario Balotelli.