SPOILER WARNING: This article contains major spoilers for "Next of Kin," the latest episode of Arrow.

John "Dig" Diggle has a secret. In the Arrow Season 5 finale, he was badly injured in Lian Yu's explosion and developed degenerative nerve damage in his right arm, compromising his ability in the field. Nevertheless, he kept this a secret from the team and even agreed to take over the Green Arrow mantle from Oliver. By the time he swung into action in "Next of Kin," the latest episode, his nerve damage had all but disappeared -- but only because he is taking an illicit drug to suppress his symptoms.

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"Next of Kin" saw Dig take over as team leader for the first time, and -- though he did stumble along the way -- his problems were more psychological than physical. He hesitated to make a crucial decision, but he was able to engage in combat just fine. By the end of the episode, even Dinah -- who had previously expressed her disapproval of his secret-keeping -- admitted that he had done a fine job.

However, Dig's ability to overcome his injuries is more than mind over matter. The final scene of the episode found him in a dark alley, where he met a man wearing a suit and carrying a briefcase. Dig handed the man of wad of cash and took the briefcase. When the man walked off with the money, he opened the briefcase and pulled out what was inside: vials of medicine. Dig then proceeded to remove one of the vials and inject it into his bad arm, steadying the tremor.

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Considering his method of purchase, Dig's newfound cure isn't exactly legal. While it's unclear how exactly he came across this medicine, it is abundantly clear that he will go to great lengths to hide his injury from the rest of the team. So far, it looks like Dig hasn't experienced any adverse side effects from this drug, though that could very well change in the future. After all, we know Dig won't be Green Arrow forever. Until then, though, he can enjoy the sweet new crossbow Felicity and Curtis developed just for him.

Starring Stephen Amell as the Emerald Archer (well, not currently), Arrow airs Thursdays at 9pm ET/PT on The CW. The series also stars Emily Bett Rickards, David Ramsey, Willa Holland and more.