The ninth season finale of CSI airs on Thursday, May 14.

As previously reported, the episode "All In" will throw Langston into the kind of field operation to which he's unaccustomed.

Look for Cynthia Watros, best known as tail-end survivor Libby on Lost, to guest star on the installment, which centers around a series of murders related to missing poker chips.

Click on the pictures below for an early look at the season finale:

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