Private Practice

Following her mother's suicide, Private Practice's Addison (Kate Walsh) will go into a dark place that may threaten her relationship with Sam (Taye Diggs).

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"She found Bizzy [JoBeth Williams] just after she killed herself, so it's pretty intense," Walsh tells TVGuide.com. "It's a real challenge to play someone who is shutting down and WASPing out, if there is such a verb."

Addison, along with Sam and the whole crew (minus Sheldon and Violet, who are working on a death row case), head to Connecticut for the funeral, where The Captain (Stephen Collins) and Archer (Grant Show) have drowned their grief in alcohol. "Everyone plays their role in a funeral, and in this case, it's managing her alcoholic family. It's really funny, but also so sad and dark."

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Addison initially won't reveal the truth behind her mother's death. "Addison's ashamed, and feels guilty and that it's her fault," Walsh says. "There's such an intense dynamic between Bizzy and Addison, with her always trying to get her mother's approval. Just when they finally get to that point of some sort of peace and understanding, she kills herself and it's really tragic."

After a push from Cooper (Paul Adelstein), who dealt with a broken Charlotte (KaDee Strickland) following her father's death, Sam will try to shake Addison out of this funk.

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"You see them work through this," Walsh says. "She finally loses it with Sam and he gets through to her. That's what I love about 'AddiSam,' he's man enough for her. She's very stubborn, and he can sway her to his will."

Private Practice airs Thursdays at 10/9c on ABC.