Desperate measures are taken when a loved one goes missing on The Lying Game. "The Grave Truth" is the tenth episode of the show's second season.
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The Lying Game Season 2 Episode 10 Quotes

Laurel: I mean, we suspected it.
Emma: I know but he confirmed it, Laurel. We're sisters. We're related by blood.

Alec, he's the one that arranged your whole adoption, under the table of course. And I know that was wrong but how can I regret that? It gave me you.

Ted [to Emma]