When Season 4 of Arrow ended, Diggle had reenlisted in the military, and we saw him saying goodbye to his family. Fans were left to wonder how his decision would change both his character and the show. For as long as we've known him, he's been the voice of reason for Oliver. He'd been a sounding board, a confidante, and a friend. But Diggle suffered a crucible of his own this season, and though some might think it was when he was forced to kill his younger brother, Andy Diggle, I think it happened when Diggle realized his brother had betrayed him.
Diggle believed in Andy long after Oliver had lost trust in him. John even turned a gun on the man who'd been his best friend for three years. And because of Andy's deceit, Laurel died, and Diggle carried the burden of guilt. It was that betrayal that changed him, and he saw a darkness inside himself much like what Arrow saw on Lian Yu. It was that darkness that led him down a dangerous path.
Diggle Tries To Kill Ruve Adams, The Mayor Of Star City
Though all of us might have been cheering at the thought of Ruve's impending death, Oliver knew this wasn't the Diggle he knew. John Diggle did not kill in cold blood. He was an honorable man, but he lost himself after Andy's betrayal, and had Oliver not stopped him, he would have the Mayor of Star City. And his brother would have succeeded in stripping him of everything.
Diggle Kills Andy
It was this moment where the change in John is reflected in his eyes. Here is this strong man who believes in justice and honor kneeling next to the body of his dead brother. Though he didn't have a choice (not with Andy threatening his family), it's still a devastating blow to this honorable man to have taken the life of the only sibling he had left.
Diggle Admits He's Lost All Hope
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Never did I ever expect to hear these words from John Diggle. He has always been the one to lift Oliver up, to provide a glimmer of hope when things look the darkest, and to stand in the face of adversary and believe they're still going to win. After all, it was John who told Oliver in Season 1, Episode 4 that Oliver needed someone to save him. Diggle knew about the ravages of war and what it could do to a man.
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And none of us can ever forget Diggle's words to Oliver in that show-changing scene.
Now it's Diggle's turn to need someone to remind him. I hope Oliver can do just that and bring back the Diggle we know and love. It might take some time, but we need John Diggle to find that glimmer of hope he's had through four seasons. With more darkness around the corner, the city will need the light more than ever, and while Oliver Queen might be the city's salvation, John Diggle is the team's.