A thief breaks into the Dempsey & Magruta Law Offices, smashes the photos on the walls, and then steals a folder containing evidence of code violations at tenement.
Lobo is painting protest graffiti against slumlord Victor Kasanti when two policemen arrest him. MacGyver gets him out of jail and Lobo explains that Kasanti is evicting his grandmother Gloria Diaz from her apartment. MacGyver drives over to help her move her possessions.
Kasanti is collecting rent when he sees one of Lobo's graffiti pieces. He meets with Andrew Lawton, a building magnate who couldn't start demolition of the slums while Gloria was contesting her eviction. Thanks to the thief, Gloria's lawyers have no evidence and the courts have okayed Gloria's eviction. Kasanti and Lawton watch as security guards put Gloria's possessions out on the street. Kasanti promises Lawton that the urban renewal project won't meet with any further delays.
Helen Dempsey and Rose Magruta, Gloria's lawyers, arrive to explain about how the thief stole their evidence. Kasanti's right-hand man Stroud has his men bring out the last of Gloria's possessions and tells her to leave. MacGyver offers to do what he can to find new evidence against Kasanti and borrows Rose's camera. As MacGyver and Lobo leave, Stroud overhears their conversation and calls someone.
Inside the tenement, Lobo explains about how he was raised in the tenement and Gloria is the only family he has left. Kasanti arrives and goes inside to tell MacGyver that he's trespassing. MacGyver refuses to leave and tells him to call the police if he has to. The landlord sends in Stroud and his thugs and MacGyver and Lobo flee to the roof. They jump from rooftop to rooftop and then descend a fire escape to get away.
At the law office, MacGyver gives the lawyers the photos. Rose and Helen explain that Lawton is building a new plaza which will raise the land values. Kasanti stands to make a profit by selling his buildings. MacGyver goes to see Lawton, who helped construct the ecologically-friendly Phoenix Foundation building. The magnate defends his actions, insisting that he'll be improving the quality of life for the residents. MacGyver points out that the residents won't be able to afford the new apartments and landlords like Kasanti are skirting the law to toss the current residents out. Lawton angrily insists it's none of his business as long as Kasanti stays within the law, but MacGyver warns that he plans to support Gloria when she files a new appeal. As he goes, Lawton calls Kasanti.
Back at the law office, MacGyver tells Lobo and the lawyers what happened, and admits he's disappointed with Lawton. Rose and Helen go over the reports from the four inspectors who confirmed that Kasanti's buildings were up to code. However, MacGyver has his doubts and goes to the building & safety department along with Lobo. The clerk confirms that all four inspectors have left the department. They meet with Clinton Ferris, the department director, who ushers them into his office and shows them pictures of his dog, Lord Jim, that he has bred and featured in competitions. Ferris explains that it's a common technique for someone to bribe an inspector to file false reports and forge the names of inspectors who are no longer accountable. He promises to look into the matter and make sure that whoever Kasanti bribed is caught and convicted.
MacGyver and Lobo go back to meet with the lawyers, who have determined that Kasanti has a silent partner. Kasanti calls to ask MacGyver to meet with him at Gloria's tenement building in an hour so they can come to some kind of arrangement. MacGyver and Lobo go there and hear Kasanti upstairs arguing with someone. When they go to investigate, they discover that Kasanti is dead, apparently killed by a falling pipe. The police take their statement but don't believe that MacGyver and Lobo heard anything. Rose and Helen arrive and Lobo wonders if Lawton had Kasanti killed. MacGyver isn't convinced and insists that they need to let the law handle things. After his grandmother's eviction, Lobo doesn't believe the law will do anything. As he leaves on his own, MacGyver realizes that they have to find Kasanti's partner.
That night, MacGyver sneaks into Kasanti's office. He finds a pile of cancelled checks in the landlord's desk and takes one with him. Outside, Stroud's men report to their boss that MacGyver took something out of the desk but they don't know what.
The next day, MacGyver takes the checks to Mo Nomitz, an ex-con and forger. MacGyver asks him to check the signatures on the checks against the inspectors' signatures. As he waits, MacGyver turns the TV to a news station carrying Lawton's press conference to announce that his project is going forward. Lobo comes in and opens the drapes, revealing the anti-Lawton graffiti he's painted on the wall opposite. As Mo confirms that all of the signatures are the same, MacGyver watches as Lobo condemns Lawton and then runs out before the guards can capture him. Lawton angrily denies any wrongdoing to the news reporter, and MacGyver leaves. Back at his jeep he gets a call from Lobo. Lobo says he wants to turn himself in and has found evidence to confirm that Gloria was illegally evicted. MacGyver agrees to meet him at Gloria's apartment. At the other end, Stroud congratulates Lobo on luring MacGyver in.
When MacGyver arrives at Gloria's apartment, Stroud and his men capture him and use plastic ties to restrain him and Lobo. MacGyver has figured out from the checks who Stroud is working for: Ferris. Ferris comes in and MacGyver explains that the phony businesses on Kasanti's checks were named after Ferris' prize-winning dog. Ferris explains that he had Kasanti killed when the landlord started to panic. He has Stroud places an explosive charge on a canister of nitrates and leaves with his men. Once they're gone, MacGyver uses an electric heater to burn through the plastic ties and free himself. When he can't defuse the bomb, MacGyver drops it down a waste disposal chute and into the path of Ferris' car. The bomb goes off and sends the car flying, stunning Ferris and his men.
Later, Lawton announces that he's putting his construction project ton hold until he has made sure that all of the tenement residents have new housing. He asks Gloria to move in first and she gladly agrees as long as he covers her moving expenses.