Mireille Enos Mireille Enos

What was Rosie Larsen doing at a casino?

After losing her top suspect, her fiancée and many hours of sleep, Detective Sarah Linden (Mireille Enos) finally caught a break in the final moments of last week's episode of The Killing. On a run to clear her head, Sarah figured out that the mysterious "Adela" Rosie had written about wasn't a person, but a ferry traveling to a casino (with a logo that matched one of Rosie's key chains nonetheless).

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Jackpot? Not so fast. Sarah quickly hits a snag in the investigation when she enters the casino looking for answers in this Sunday's episode (10/9c, AMC).

Check out this sneak peek to find out: