Both Sarah Kidwell and Lisa Neary are mourning the deaths of their husbands -- Marine Majors Jim Kidwell and Steve Neary -- although the wives have received only sealed caskets and no details of the secretive circumstances regarding their spouses’ killings. Their situation becomes more dire and distressing when, at the reception after her husband’s funeral, Sarah receives a phone call from a man claiming to be him.
Gibbs (MARK HARMON), Kate (SASHA ALEXANDER) and Tony (MICHAEL WEATHERLY) are called in to investigate whether the call is a hoax or Kidwell is still alive. Their initial efforts lead them to the men’s commanding officer, Lt. Colonel Walsh. He says that the men’s case has been kept secret to keep their honor intact. They had been undercover in Colombia and – soaking up the local color – were actually killed by a prostitute there who poisoned them with formaldehyde. While he’s not sure they believe that story, Gibbs then realizes that the Walsh they’ve been speaking to is an impostor. Working together, the three agents come up with a composite drawing of the man, and decide that he may hold the key to Kidwell’s and Neary’s whereabouts. Then, Gibbs discovers that one of Kidwell’s friends has a tape with a message from a man claiming to be Kidwell too. When Abby (PAULEY PERRETTE) runs voice comparison tests with the tape and videotapes taken from Kidwell’s home, she says they match. That assertion leads Gibbs and the others to realize Kidwell may not be dead after all.
Now looking in the caskets, the agents find Kidwell’s body in his, but only concrete blocks in Neary’s. Worse, Kidwell’s eerily healthy countenance gives Ducky (DAVID McCALLUM) few clues to how he died. Ducky’s autopsy then leads to a harrowing conclusion: Kidwell was murdered, as he was embalmed while still alive.
Knowing that Neary may still be alive, Gibbs has all the more reason to suspect the impostor’s involvement in Tidwell’s death and Neary’s vanishing, particularly when he receives a disturbing call from Lisa Neary. She is currently upset that Tony is harassing her. But with Tony standing near him, Gibbs knows that their imposter is now impersonating the NCIS agent. Gibbs hurriedly rushes to Lisa’s location, just in time to spot the imposter fleeing but drawing a gun to shoot Gibbs, narrowly missing him.
Meanwhile, with Abby’s computer skills, the agents identify the impostor as CIA Agent Chuck Canton. The CIA claims that Neary and Kidwell had been kidnapped while trying to bust up a Colombian cartel. While their two million dollar ransom was paid, they were still killed. However, when Gibbs learns that Canton was supposed to make the payoff to spare the men’s lives, he deduces that Canton took off with the two million dollars. Worse, when Neary and Kidwell still lived, he hatched a scheme to murder them so he could keep the money. Since embalmers use formaldehyde, his story of how they died would pass muster and embalming them while still alive wouldn’t reveal the timing of their deaths.
Certain that Neary could be about to meet a similar fate as Kidwell, the agents get a tip from the CIA as to where in Colombia Neary might be. There, they find that Canton has ordered him to face the same grim demise as Kidwell. Just as a mortician is about to embalm him, the agents burst in. While Canton tries to thwart them and keep his plan intact to abscond with the money and kill Neary, the agents stop Canton with gunfire while saving Neary.