Travelling to Malta in search of answers about his father's past, Alex and his best friends uncover the beginnings of a deadly plot by the criminal cabal known as Scorpia and the identity of its charismatic and ambitious new leader.

Alex is sent on a mission for Scorpia to prove his loyalty, with Tom and Kyra following close behind hoping to rescue him. Meanwhile, the Department attempts to unlock the secret of 'Invisible Sword'.

Alex returns home with a dark mission of revenge. Jack, Tom, and Kyra must enlist the help of unlikely allies to save Alex before he commits to Scorpia forever.