Sherry Stringfield

The (former) doctor is in on CSI.

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alum Sherry Stringfield guest-stars on Wednesday's episode as Dawn, a blue-collar swing-shift CSI who helps Morgan (Elisabeth Harnois) track a serial rapist. As you can see in our exclusive first look video from the episode below, Stringfield is as good at spouting out forensics jargon as she was medical lingo. However, the evidence Dawn and Morgan have collected isn't providing many answers.

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Meanwhile, Dawn is is also wrestling with problems that have nothing to do with the case. When Dawn sees a young man walking through the lab, she is reminded of her teenage son, whom she's had to kick out of her house because of his drug addiction.

How is she coping? And have Dawn and Morgan found a new lead to help in their investigation? Click play below to find out!

CSI airs Wednesdays at 10/9c on CBS.

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