In Richmond, Virginia, an injured Navy lieutenant grabs a jug of caustic drain cleaner, chugs it, and drops dead; Gibbs and company investigate; Tony soon learns about some of the recent behavior of the victim. While Ducky and Palmer head back toward Washington, DC, in their van, one tire blows out; three people detain them, take them to a secluded cabin, and require Ducky to perform an improvised autopsy there. Meanwhile Abby learns about the location and behavior of the victim just before he died, and the team trace the van. Tony learns about the peculiar circumstances of the victim, and Abby confirms that things do not jibe; she also traces some of his activities; she further deduces who roughed up the vic before he died; the gang find the assailant, and he tells Gibbs why. The gang follow Duck and Palmer into a forest, find one dead bad guy, then find the dynamic duo and seize the other bad guy. The bad woman takes Palmer's bait, then the team grab her as expected.