Revenge's Charlotte Clarke will come back from rehab will a nuclear level bombshell.

'Revenge' Finale: Who Will Die In 'Two Graves' [POLL]? EP Teases Upcoming Deaths

The illegitimate child of David Clarke and Victoria Grayson will be on hand as Emily Thorne's story comes to an end in "Two Graves," but the wayward character may also add a little fuel to a blaze that is already out of control.

"She delivers a huge piece of information near the end of the episode," showrunner Sunil Nayar informed TV Line. "I can guarantee it will generate conversation."

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Now that Emily's life is in shambles, Victoria is (not actually) dead, and David is knocking at death's door, Nayar didn't think it would be right to leave Throne's half-sister out of the fray. Instead, the EP indicates that the sibling's upcoming interactions will be very telling.

"When we talked about the idea of the series ending, we thought it's really hard to end it without her being a major part of the story because she's part of both of these families and because the story has to be told to her," Nayar told Entertainment Weekly. "How you see Charlotte dealing with Victoria's death puts her in a certain place of mind. She has a king of significant role and has a huge piece of information in the finale that I think is really delicious."

Find out more when Revenge airs its series finale airs May 10 at 10 p.m. ET on ABC. Click the video below to see a preview for "Two Graves."