The promo for the fall finale of season 4 of Arrow reveals that Felicity's (Emily Bett Rickards) life is going to be in grave danger.

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Damien Darhk has some very devious plans for Oliver (Stephen Amell) as in the clip he suggests that the best way to punish someone is by claiming a loved one, someone to fight for as her says: "as long as they're alive, you have something to fight for, that is what I am taking away from you."

Cut to Felicity being dragged away by Darhk's men and the tag line revealing that the finale will leave you breathless, is corroborated by Felicity's labored breathing, as through a glass pane, with a deathly pallor cast over her face, she is heard telling Oliver she loves him.

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There have also been strong hints about the fact that the person in the grave will be revealed in the fall finale of season 4, and after watching the preview for the next episode, it seems like Felicity might be a strong candidate.

Previously in an interview with TVLine, Arrow's executive producer Wendy Mericle spoke about when fans might find out about the person in the grave in season 4. Mericle didn't give a definite timeline, only teasing the possible reveals suggesting that there might be more flash-forwards "here and there... right around midseason."

"We're definitely toying with that," Mericle said, "and when and if we do decide to do that, it will reveal even more pertinent information about not who's going to be in the grave but certainly where our characters are when that [death] happens." she added.

Damien Darhk will strike in this episode, titled 'Dark Waters.'

Here's the official synopsis:

"After the city is attacked again, Oliver (Stephen Amell) makes a bold move against HIVE. Malcolm (John Barrowman) checks in on Thea (Willa Holland) andleaves her with a warning. Things take a horrible turn when Damien Darhk (guest star Neal McDonough) retaliates in a brutal manner at Oliver's mayoral holiday party."

'Dark Waters' will air on December 9 on The CW.