Mac and Jack are locked in a cage looking at a dog holding the keys in its mouth. Jack tries to call it over but the dog ignores him. The door is rigged with explosives if they try to open it, and Jack gets an idea. He grabs a bone from the bottom of the cage and lures it over. However, it drops the keys to do so. Mac rips apart a boot and attaches the sole to his belt, and uses it to try and snag the key. The dog grabs it and runs off.
Later back in LA, Billy picks up Riley in a new Bentley ad says that it's a long drive from L A to Dallas. They kiss and get in, and Billy explains that he got it from a runner who skipped bail. They put on sunglasses and drive off.
Jack arrives at Mac's place and finds Mac, Wilt, and Leanna having a plank contest to decide what they're having or lunch. Leanna says that she threw out Jack's old sandwich, while Mac and wilt both collapse and Leanna wins. Jack calls Mac over and points out that Leanna is cleaning the refrigerator and figures that soon she'll be moving in and changing everything. Matty calls to tell them to get mobile and she'll brief them in mid-flight.
Leanna goes to Phoenix and on the jet, Matty tells the team that the CDC asked for their help and they have an "inventory discrepancy". She figures that something serious is going on. The three men arrive at the CDC base in Atlanta and Dr. Falama tells them that a level 4 vial disappeared from a high-security facility. It's a strain of a deadly virus, Specimen 234. It has a 99% mortality rate s, and they believe it went missing the day before when a containment unit holding experimental subjects wasn't latched properly. Falama shows them the surveillance footage revealing that the rats escaped their cave. Four hours later they discovered the vial's absence. She needs 234 found quickly and quietly to avoid panic. Wilt checks the footage while Jack and Mac check out the lab.
The two men don scrubs and put on positive pressure suits, and Falama takes them into the lab. They've already interviewed the four scientists who were in the lab and came up with nothing. Mac has Falama read her the details of the incident report, including the fact that there was a pool of glycerol on the table next to the rats' cage, and then they go through the lab's exit procedure into a seven-minute chemical shower. Mac checks the suits and finds one with duct tape residue on it. There's no matching tear, and the suit is a guest suit, and Mac tells Falama that it was a heist. He explains that someone with security access entered the lab and hid the vial beneath the tape. He used a frozen rod of glycerol and exited the lab. The rod melted down and the rats escaped, providing a distraction.
The team has Wilt bring up the security footage, and Mac spots Dr. Luca with a canister that could have been filled with liquid nitrogen and used as a mobile storage facility. The men call Matty and Leanna, and tell them the situation. Luca has made heavy withdrawals in the days before the theft. Mac notes that they should run a search for biocontaminant storage facilities. Leanna discovers one that was shipped to South Carolina a week before the virus was stolen.
Driving through Arizona, Billy mentions that he went to lunch with Elwood. Billy assures Riley that Elwood loves her and is super-protective, and told Billy how he thinks family is important. Riley wonders what else Elwood said, and Billy says that she's glad Riley is giving Elwood a chance. She checks in with Matty, and Billy says that his mama called to tell Matty that Riley and Billy needed some alone time so Matty wouldn't interrupt. Billy says that he has a surprise for her at the end of the trip. They stop at a BBQ place and when they come out, discover that someone has stolen the Bentley.
The team arrives in South Carolina, and Jack talks to Wilt about how Leanna is coming over. He complains about Leanna throwing out his sandwich, and Mac interrupts to say they should focus on the case. They arrive at the shipping address and discover that it's a parking lot. There's an RV parked nearby and Mac figures that Luca bought it to use as a mobile storage lab. Matty checks it by satellite and confirms that no one is inside.
Mac rigs up protective masks out of parts in the trunk, and they go inside. The containment unit is there but empty, and they find a burned passport in the sink. There's also a burned vial, and wilt finds Luca's laptop. It's open to a video of Luca saying that he's sorry for what he's about to do and hopes that he'll be forgiven. He tells Geofri that he's coming home. According to Luca's file, Geofri was Luca's brother in Rumania, and died in a mining accident several months ago. In the video, Luca injects himself with the virus. Mac tells the others that there's a 24-hour incubation period, and Mac figures that they have to get to Rumania and find Luca before the 24 hours run out.
After calling in the police and getting no help, Riley considers calling for a plane. Billy says that they should improvise and calls a ride-share to Dallas. He gets a hook-up and says that he's looking forward to seeing the look on Riley's face when she sees the surprise. Someone drives by in the Bentley, and the rideshare driver arrives. Billy pays him $67 to follow the Bentley.
The drive takes the Bentley to a garage, and Riley and Billy figure that it's a chop shop. Billy figures the police will take too long, and suggests that they steal the car back.
The team arrives in Rumania, and Matty and Leanna say that according to the surveillance footage, he arrived but then disappeared into the crowd. Mac searches the restroom and finds a duffle bag with a wig. They go to the nearby grocery store to get some supplies for Mac, who mixes them and then sprays the taxi headrests. One headrest turns red, and Mac gets directions from the cabbie to where he dropped Luca off. It's a quiet suburban house, and they knock at the door. There's no answer to Mac picks the lock and they go in. They hear banging and follow the noise, and discover that the door is glued shut. Jack kicks the door in, and they find a man who is tied up and looks just like the disguised Luca. The man, Sala, explains that Luca came there disguised as him and jumped him. Sala is a reporter and discovers that his camera has been stolen, and explains that he was going to an award ceremony for Dorin Ionescu at his house that night. Wilt confirms that Ionescu owned the mining company where Geofri died and was blamed for the unsafe working conditions, and they realize that it's an assassination attempt.
Riley and Billy peer in the window and see the mechanic preparing to take the Bentley apart. The mechanic starts a powered impact wrench, and Riley shuts off the power. When the mechanic goes out to investigate, Riley and Billy jack open the garage door. Riley ties a live electrical cable around the doorknob to keep it shut, and then starts the car as Billy opens the garage door. She drives out and picks up Billy, and they drive off as the mechanic arrives.
Matty tells Mac that the government can't get a Hazmat team there in less than 30 minutes. There are over a hundred people at the party, and the security won't listen to Jack. Mac figures that security is lighter at the back and they go thee after digging through the neighbor's garbage. He uses a bag to create an air wedge and opens the door, hands out sedatives, and tells the others that they have to subdue Luca until the Hazmat team gets there.
The team goes in posing as reporters and waiters and look for Luca. A guard spots Wilt and says that he doesn't recognize him, and starts to take him away. Wilt injects him with the sedative and warns the others that he had to use his, and Mac spots Luca heading for the green room where Ionescu is. Jack attacks the guards to create a distraction,, and Mac knocks out the remaining guard in the green room. Luca is there taking photos of Ionescu, and Mac realizes that Luca is contagious.
Matty calls Wilt and says that the Hazmat is ten minutes out.
Luca tells Ionescu to move over with him. Mac runs in and tells them not to let Luca touch them, and Luca insists that Ionescu is a monster and doesn't deserve to live. As the guards get Ionescu out, Luca tells Mac that Ionescu's men rigged the mine to collapse so he could get the insurance. He insists that it was just supposed to be Ionescu. Mac knocks him back with a case, wraps him a tarp, injects him with the sedative, and shoves him into a closet. Jack and Wilt arrive, and they tape a second tarp over the door to contain the virus.
The Hazmat and the police arrive, and the police find evidence of Ionescu's guilt. The team watch the two men being driven away, and wilt says that they should go home. Mac warns that he doesn't know how long it will be until they're allowed to leave.
Later back in LA, Mac and Wil assure Jack that he's clear. Jack doesn't believe it, and Mac gives him a swab. Matty and Leanna come in and Leanna gives Jack a replacement sandwich and assures him that she missed up the refrigerator. Mac says that the test came back positive, and tells Jack to go to the interrogation room and lock himself in. Once he leaves, Mac admits that he made up the whole thing.
Billy drives Riley to a suburban home and explains that one of Elwood's biggest regrets was turning his back on the family. He takes Riley to the front door and says that Elwood fought with Riley's mother and didn't want to get back together with her until he straightened out his life. Delores answers the door and Billy introduces her to her granddaughter Riley.
Written by Gadfly on Dec 1, 2018