Team "Arrow" may have saved the world at the end of Season 4, but old wounds still have a long way to go before they heal. Case in point is Quentin Lance (Paul Blackthorne), who lost his job and is suffering from the death of his daughter Laurel (Katie Cassidy).

Though Blackthorne previously told Zap2it that Donna Smoak (Charlotte Ross) would be Lance's salvation from the dark times, that may not be a long term solution.

RELATED: Oliver and Felicity have very different ideas about ‘Arrow’s’ new team

"It's the dark days for Lance. Suffering, the demons -- they're back," Blackthorne teases about Season 5. "His default setting is 'it's my fault.' If anything questionable happens, he tends to sort of blame himself. He's doing that to some degree with Laurel's death. I hate to say it, but there's miserable days ahead for Lance right now."

While Blackthorne admits that Donna was a "little flash of light" for Lance at the end of last season, it remains to be seen what the state of their relationship it now. "Whether that has longevity, we'll have to see," he says.

Given Lance's history of alcohol issues -- especially when faced with a tragedy like losing a child -- there is certainly some doubt to be cast on whether he and Donna can weather this particular storm.

RELATED: What’s bringing ‘The Flash,’ ‘Supergirl,’ ‘Arrow’ & ‘Legends of Tomorrow’ together so soon?

If the dark days to come are as bad as Blackthorne says they are, at a certain point Donna would have to remove herself from that situation. There's truly only one person who can fix Lance and that's himself. Hopefully he's able too.

"Arrow" returns Wednesday, Oct. 5 at 8 p.m. ET/PT on The CW.