Sometimes the strongest evidence is right under your nose. Or, in the case of NCIS' Tim McGee (Sean Murray), right under your bed. And no, we're not talking about his dad's ashes.

On Tuesday's episode, McGee learned the hard way why you shouldn't move into an apartment whose previous occupant was a serial killer. After his apartment is ransacked, McGee discovers that his predecessor buried a long-lost fugitive named Logan Pruitt under the floorboards in order to hide a key that will lead to a fortune's worth of diamonds.

The killer tries to bargain with McGee and Gibbs (Mark Harmon) to get a bigger cell in exchange for information about where the key is, and after a tip from his girlfriend, Torres (Wilmer Valderrama) and Quinn (Jennifer Esposito) discover the stash of diamonds in a safety deposit box. And, luckily for McGee, takes the news that they've been sharing their living space with a dead body in stride.

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With a politician's nose for opportunity, Congresswoman Jenna Flemming (Mary Stuart Masterson) jumps in, advising Gibbs to take the deal and Vance (Rocky Carroll) to "crack the case" and use his subsequent elevated position to kick off a campaign for political office. But Vance resents the suggestion -- both of them, really -- and after a few tense moments, Flemming backs off.

Unfortunately, in their back-and-forth, Vance manages to personally insult Flemming by accusing her of "dancing with the devil" simply by being an elected official, so she tells him that she wants to "take a step back" from their relationship -- for now.

NCIS airs Tuesdays at 8/7c on CBS.

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