Arrow's John "Dig" Diggle has a big secret that will pose a threat to his teammates. In "Next of Kin," Diggle "cured" his degenerative nerve damage with an illicit drug, and it looks like this dirty little secret will come back to bite him. During a set visit, Diggle actor David Ramsey teased how his character's drug use will impact the team as well as his family, including his wife Lyla.

Asked about Diggle's secret drug use, Ramsey said, "I think it’s a six episode thing, it’s around five or six episodes. This is going to be a situation where Diggle’s life is threatened because of this. The team has already been jeopardized by Diggle’s indecision, but it’s going to go further with his drug use. So I think he has to come clean at some point to his wife and to his team. I think around episode 6 or 7 it all comes to a head. A tragic, tragic head..."

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"He’s never held secrets like this before," he explained. "This is a man whose moral center plays such a paramount role in his life that he was willing to stay in jail because of how he felt about killing his brother, and how that lead to the death of the Canary. So this is a very moral man. So again I point to the importance that he holds, how important and relevant holding the mantle of the Green Arrow is to him. The writers have put that nugget into the last season in the crossover, and it’s paying off now."

"I think it’s interesting for Diggle that last year’s crossover had the Dominators, and in that illusion they went into our heads and brought out what would be our greatest lives. And for Oliver, he got to correct a mistake he made with Laurel and get married, and for Diggle it was being the Green Arrow," he added. "I think that’s a very interesting story, that somehow, some place in Diggle, he likes wearing the hood."

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He also revealed that Diggle's wife Lyla will soon return on the series. "Lyla comes back pretty soon, and Diggle has to face her, he’s lied to her as well," he shared. "But there’s a nice moment in the episode I think last week or the week before last, where Oliver comes and tells Diggle that 'I know you have a family too and maybe I shouldn’t have asked you that,' so I’m happy they addressed that as quickly as they did. It’s kind of a sticky point in the story. But Diggle is probably the most mature of this group, and he’s come to peace with his family and what they do together and where that could possibly put his son. So I hope we’ve buried that as far as that storyline. I don’t know what the theme of this season is, but it should be trust, because that’s going to be a recurring theme this season. There was some stuff we’re shooting today was all about trust, so that theme is going to continue in the big reveal for Dinah and with Diggle’s story, Oliver, Felicity, it will continue throughout the season. We always have a theme for the season."

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.