Revenge fans should prepare themselves for a stressful midseason hiatus.

Episode 410 will air as the midseason finale, and the untitled installment will prove to be one of the most important stories Revenge has told to date.

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"As it turns out, ep 410 is 1 of the biggest eps in #revenge lore #whoknew #yikes," tweeted writer Ted Sullivan on Wednesday.

A major game changer is coming in episode 5, "Repercussions," but it sounds like the winter finale will top the upcoming shakeup.

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"Read the outline last night faster than any outline before it," said post-production coordinator Lizzie Donaldson said of episode 10. "Couldn't come up for air until I was done."

Meanwhile, David Clarke (James Tupper) has yet to find out his daughter is still alive. Victoria (Madeleine Stowe) is building up to a deadly family reunion in "Ashes," and the Queen of the Hamptons may turn her new beau against his Emily Thorne without him ever knowing her true identity.

Find out more when Revenge airs Sundays at 10 p.m. ET on ABC. Click the video below to see a sneak peek of "Ashes."

Tags: Revenge television ABC