The CBI investigates in a case involving academia and a graduate student at a natural history museum to see if these students are into more than just academics.
Castle and Beckett's unsuccessful meet-the-parents dinner leaves them arguing, even as they must head out to recover a murder witness. A surprise attack leaves them and the witness on the run without a phone or a gun. The two must find a way to keep the witness safe, if they don't kill each other first.
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