Football superstar James Graham begins a gripping journey to confront sport’s hottest issue: concussion. In this series, we’ll meet the stars of AFL, Olympic sports and rugby union as they face the truth about head trauma.

Graham, one of rugby league’s greatest ever hard men, reveals the day he feared he was losing his mind, even as he was fulfilling the dream of stardom born in his Liverpool childhood. And we meet league stars including Immortal Wally Lewis, who reveals a shocking secret.