A dead Navy Commander, Brian Farrell, washes up ashore on North Virginia Beach and when two drug runners have met the same fate nearby, immediate speculation connects the murders – especially since both Farrell’s boat and the dealers have been mercilessly shot. But despite the DEA’s and local law enforcement’s claims that the deaths are linked, Gibbs (MARK HARMON) isn’t so sure. At the dealers’ crime scene, Gibbs finds that they – whose boat hasn’t been recovered – were carrying thick stacks of hundred dollar bills. When Gibbs learns the bills are actually counterfeit, he asks Kate (SASHA ALEXANDER) to talk to her Secret Service contacts to find out if they might have a lead on who might have forged them.
Gibbs becomes more motivated to clear Farrell’s name in any drug connection when he discovers that the commander was involved in an anti-drug program for urban high school kids. Abby’s (PAULEY PERRETTE) testing proves that the same weapon killed Commander Farrell and the drug dealers but while the dealers had gun residue on their hands, the commander was clean. From that, the team deduces that Farrell – while fishing -- had become innocently caught in the crossfire of the dealers and some other suspect.
In his next move, Gibbs works with the DEA to bring in the boss and rival boss of the drug runners in hopes of uncovering more clues. From that interrogation, Gibbs manages to elicit the identities of the runners, Jesus and Carlos Garcia, and the fact that they’ve been hauling drug smugglers, illegal immigrants or gunrunners. The Garcias’ drug boss also leads Gibbs to the boat at a marina. There, he and Tony (MICHAEL WEATHERLY) find a gruesome crime scene with bloodstains and bullet holes. From an interview with two women on a nearby docked boat, Tony learns that a man was on the boat that morning and another man in a white van pulled up to pick him up.
Then, startling information comes back regarding the forged bills in that the serial numbers matched a batch of bogus bills passed by 9/11 hijackers. This discovery leads the team to realize that their culprits aren’t drug dealers, but rather, terrorists, and the FBI are now drawn into the case as well. Fingerprints lifted from the drug dealers’ boat identifies their killer as Seth Shakir, a foreign terrorist wanted for the U.N. bombing in Baghdad who is believed to have slipped out of Iraq a few weeks ago. Meanwhile, Tony’s further investigating turns up more information on the white van; it was actually from the Jefferson Power electric company. The FBI explains they have long worried about any power grid failure, because that could render parts of the country defenseless. When Abby informs Gibbs that she found traces of C-4 in the evidence collected on the dealers’ boat, FBI agents indeed suggest that Shakir is planning on bombing some hard target, such as a power plant. And Gibbs believes that any target hit would actually trigger a blackout from the East to the Rockies. With the threat of Shakir’s plan striking soon, Gibbs, Tony and Kate head to Jefferson Power. There, at a transmission tower, they spot Seth molding C-4 around a tower leg. They exchange gunfire with him... and succeed in stopping his plan in the nick of time.
With Abby finding signs of battery acid being spilled on Fuentes’ parachute lines, Gibbs and Tony take a look at the paraloft where the chutes and reserves are locked and stowed. The investigation quickly points to the chutes’ rigger, Lance Corporal Billy Webb who, Gibb discovers, has had a previous record for robberies, and actually even served jail time. His record has even spawned a nickname that often provoked threats from him toward his Marine cohorts. Still, Abby’s preliminary findings uncover that the logs to check the parachute equipment seem to have forged signatures for Webb, and that there are two sets of fingerprints on the deployment bags’ knots. With that, Gibb tries to tap into the Armed Forces’ DNA Registry to identify the names behind the prints. While Lt. Bud Roberts (guest star PATRICK LABYORTEAUX) knows that database can’t be accessed for suspect information, he does agree to help Gibb with search warrants for several corporals’ lockers in the paraloft.
During that search, the case becomes more complicated as an exacto knife is found in rigger Lance Corporal Schilz’s locker. But when Kate and Gibb question him, a shell- shocked Schilz unflinchingly agrees to a DNA test. With Abby backlogged, Gibbs assigns Kate to help her, and the two quickly forge a friendship while performing more forensics testing. They determine that Fuentes’ suspension lines were cut, possibly with the exacto knife that’s been found. Then, when keys to the paraloft are.
found in Webb’s footlocker, Gibbs’ suspicions are focused on him again. During Webb’s questioning, he vehemently claims innocence, but lets Gibbs know he doesn’t believe Schilz is guilty either. Abby’s further findings vindicate Webb; his fingerprints don’t match those found on the rigging. However, there are Schilz’s and another unidentified set.
Armed with this information and losing out on Webb as prime suspect, Gibbs thinks somebody targeted Fuentes, trying to hide a murder behind sabotage. He focuses on Fuentes’ behavior once again, and wonders about all his previous, “lucky” accidents. Delving into them, the agents find a series of recent accidents that plagued Fuentes, but all miraculously left him unscathed. And upon remembering the corporals’ reference his luck at the poker table, they find that Fuentes’ checking account has been routinely pumped up with frequent cash infusions. The agents then begin to piece together that those poker games may have left one of the other corporals in serious debt, and – to avoid it -- he could have resorted to murder, rigging a parachute to end both Fuentes’ life and money troubles.
With Fuentes lucky streak in mind, Gibbs deduces that drawing “13” to parachute in – while deemed unlucky for many – wouldn’t have mattered to Fuentes. And that was indeed the number on his reserve chute. So, with the tampered chute, Gibbs and Tony take to a C-130 with all the suspected corporals for a mission. There, high in the sky, Gibbs asks Dafelmair if he wouldn’t mind taking chute 13. Although Dafelmair doesn’t seem to mind at first, his confidence soon crumples and – not eager to skydive to his death – he admits to killing Fuentes. In his confession, he identifies angry accomplice Ramsey, who was also eager to get out of debt and conspired with him.
And all through the case, Gibbs tries desperately to avoid the continual bleat of his cell phone, with ex-wife number three eager to reunite on the other end.