Lt. Ruiz assigns Jack and Dan to a case involving the elusive "Tech Bandit" - the prime suspect in a recent software burglary at the local Nygen Technology firm - but only as the assistants to famous forensics expert Dr. Alphonse LaViolette. Dan doesn't like this, but these orders come straight from the Chief.
LaViolette swaggers into the station - trailed by a student who's making a documentary film about the "great man" - and heads to the crime scene, where he'll begin his investigation. Jack and Dan point out that they already know how the burglar gained access to the building (a hole in the 10th floor) and when (a gap in the security camera footage), but LaViolette ignores all this, noting that the view from a building across the street provided the burglar with a perfect vantage point.
From there, LaViolette discovers the burglar cut himself while moving some planters; he takes a blood sample and orders Jack and Dan to take it to a lab for analysis - and fetch his lunch.
Meanwhile, Asst. D.A. Liz and a young blonde named Zoe meet with Ruiz. Zoe's been busted for prostitution by an undercover cop, but has revealed that her main client is State Senator Buddy Haverton.
Zoe witnessed Buddy take cash from Leo, who wants Buddy's subcommitee to drop an investigation into toxic waste being dumped next to a children's facility. Buddy takes the cash, but refuses to halt the investigation, making Leo furious. Zoe's willing testify to this - if the prostitution charge is dropped - but Ruiz wants her to wear a wire so that they can prove Buddy's paying for sex with taxpayers' money
Jack's unhappy being LaViolette's errand boy, but Dan did some forensic investigation of his own. He tasted the "blood" - and it's barbecue sauce from the local Hickory House restaurant (Dan's an expert on Dallas' barbecue joints). Knowing that the break-in took place at 12:45 p.m., Dan believes that the burglar ate lunch there - and the joint's security camera has the culprit on tape. And it does.
When Jack and Dan return to the station and tell LaViolette what they've found, he orders them to take a still from the tape to the local FBI office so it can be enhanced. While they're waiting, the young filmmaker wants to interview Jack and Dan. Jack declines, but Dan proudly delivers his standard "gut feeling," "old partner," and "real cops" speeches. Jack and Dan decide to stop waiting and go after the suspect - with the filmmaker in tow.
Liz and Ruiz outfit Zoe with a wire, but before she can get Buddy on tape, Leo and a thug arrive and force Buddy into agreeing to drop the investigation.
Jack rewatches footage from the barbecue joint and discovers that the suspect is a food blogger, who's staying at the Crescent Hotel. They question the hotel chef about recent picky customers and learn the suspect's name (Roland Van Hoff) and room number.
But LaViolette - using photo enhancement - has discovered the same information and, backed by a SWAT team, prepares to make the arrest himself. Meanwhile, Van Hoff, suspicions aroused by a phone call to his room, escapes out the window.
Ordered outside, Jack and Dan are bonding over vinyl vs. CDs when they see Van Hoff driving away. They jump in Dan's Trans-Am, chase, and capture him. Van Hoff's happy they - not LaViolette - caught him, explaining he became a thief to support his food blogging (because blogging, unlike crime, doesn't pay).
Meanwhile, Zoe's too freaked out to continue, so Ruiz and Liz decide to set Buddy up with another girl. But Zoe sends Buddy a camera-phone photo of Liz - and he wants only her. Liz reluctantly agrees to go undercover - in a skintight dress that brings LaViolette's argument with Jack and Dan (and everything else) to a drop-dead stop.
Buddy meets Liz at a club atop the First International Building, offers her money for sex, and Ruiz busts him. But Buddy cold-cocks Ruiz, grabs her gun, and takes Liz hostage.
Back at the station, hapless Hodges takes charge. Jack and Dan are disgusted, but when Van Hoff says that he knows a secret way into the building, they unlock his cell so he can show them.
Dan tells Jack that when you've slept with a person who's been taken hostage, you've got to rescue the hostage yourself. Jack, who's slept with Liz, realizes Dan's slept with Ruiz!
As Buddy, drinking heavily, shoots two cops, Van Hoff, Jack, and Dan enter the building though a plumbing shaft. After handcuffing Van Hoff to a pipe they don't realize is broken, Dan gets stuck, and Jack falls though the ceiling into the middle of the hostage situation.
Dodging Buddy's gunfire, Jack grabs a fallen officer's pistol, creating a standoff - until Dan crashes through the ceiling, lands on Buddy, and cuffs him.
LaViolette is furious that Jack and Dan allowed Van Hoff to escape - we see him driving to L.A. with the filmmaker, who's found a brand-new subject - but Buddy's in custody and two lives were saved, so Liz tells LaViolette to take a hike.
As Liz, Jack, Dan, and Lt. Ruiz head off to celebrate over barbecue and beers, Dan pulls Ruiz aside and confesses that he told Jack about their past liaison - but he didn't show Jack the videotape!