The Lying Game follows Emma, a kind-hearted foster kid who learns she has an identical twin sister, Sutton. Sutton, unlike Emma, was adopted by wealthy parents and is seemingly living an ideal life. After their initial meeting, Sutton talks Emma into stepping into her life for a few days while she pursues a lead on the mysterious identity of their birth mother. After Sutton inexplicably fails to return to the girls' designated meeting place, Emma must decide whether to come clean about her identity and risk her own safety in the hope of uncovering her twin sister's whereabouts, along with the truth about why they were separated in the first place. The charity gala takes a somber turn as everyone honors the memory of a loved one. Dan issues Ethan an ultimatum that has heartbreaking consequences. Emma finally confronts Rebecca about her lost childhood. Ted tries to find the right way to tell Kristin about another secret from his past. Meanwhile, an unexpected twist brings the fundraiser to a crashing halt. Ethan's confession to Dan threatens to shatter the brothers' relationship forever. Sutton receives a mysterious phone call that may provide some valuable information. Emma's feelings for Thayer are tested when she finds herself in close quarters with Ethan. And someone else comes face to face with Emma and Sutton. Everyone gathers to celebrate Dan and Theresa's wedding but the celebrations do not go off as planned. Ethan figures out who Emma is protecting and confronts her about shutting him out. Sutton's sudden change of heart confuses Emma, who isn't sure she trusts her sister. Ted's behavior grows more erratic as his family continues to fall apart. Meanwhile, in the game between Alec and Rebecca, Jordan decides whose side he's on. Emma struggles to make sense of newfound revelations and shifts in her relationships with Ethan and Thayer. After hearing Emma's suspicions about Rebecca, Sutton's faith in her mother begins to falter and she decides to take matters into her own hands. Rebecca is thrilled when Kristin and Ted's marriage continues to unravel, putting her one step closer to achieving her goal. Meanwhile, Alec realizes that Jordan could be a strong ally in his private war with his wife. The Flipside Formal offers Emma the chance to try and trap Rebecca and Sutton in a lie, but she needs Ethan's help to pull it off. Laurel struggles with where her loyalties lie, while Kristin makes a troubling discovery that has more significance than she realizes. Jordan continues to waffle between Laurel and Mads, and Theresa's defense of Alec threatens to drive a wedge between her and Dan. Meanwhile, Rebecca and Ted, and Alec and Kristin, each reminisce about old times.