Last week on Rush Hour, Lee and Carter built a foundation for their partnership. This week they’ll use that teamwork to help protect a young boy who witnessed a murder.

A graffiti artist climbs a building and starts spraying. As he’s putting his signature on the piece, he sees men in a window across the street. The Assistant District Attorney is murdered by a group of gangsters. The artist drops his flashlight and the men see him. It’s heart-pounding as he scales down the building and runs for his life. He gets away.

Lee chooses a Chinese pop song in the car. Carter tells him he needs to learn about American music.

Captain Cole meets with the DA. She calls Lee and Carter in. ADA Bertram is missing.

Bertram’s medications, phone and car are missing, but no one saw him leave. Carter notices one spot in the apartment is a mess, while the kitchen is spotless. He sees a discolored area where a rug used to be. He thinks it was used to wrap up a body. Lee says the floor smells like it’s been cleaned.

Lee notices graffiti across the street. Didi tells Carter that Bertram had been withdrawn lately. She’s not sure it was murder. She reports that two men were seen chasing another into an alley the night Bertram went missing.

Lee finds wet paint and abandoned spray cans. There’s also a bag and a swatch of fabric from the artist’s jacket. There was a witness!

Carter shows the DA footage of the witness. Lee asks to see Bertram’s case load. Cole says she’ll get it for them.

Carter goes to Gerald for information. He doesn’t know who did the painting, but he’s willing to find out.

Bertram’s paralegal says he was dedicated to his cases. Carter gets a text that they found Bertram’s body in his car in an apparent crash.

Didi says there’s no blood at Bertram’s apartment. They found animal fur and monkey feces on the artist’s bag.

Gerald sees a painting with the same signature. He questions a street merchant, but he won’t say anything. After Gerald leaves, a mobster shows up and threatens the man with a gun.

Gerald found several paintings with the same signature in areas surrounding the zoo. Didi says the fecal matter is from an extinct monkey in the nearby deserted zoo.

Lee puts in a CD of American music. It’s the Spin Doctors. Carter complains. Lee tells him the playlist is made up of Captain Cole’s favorites.

Carter, Lee and Gerald find a tent with graffiti supplies at the abandoned zoo. The artist sees them and takes off running. A car full of gangsters shows up and chases the runner. Lee and Carter slow them down. Carter covers, while Lee follows Gerald to catch the artist. It turns out to be a young boy, but he gets away.

Credit: Ron P. Jaffe/CBS ©2015 CBS Broadcasting, Inc. All Rights Reserved

Our heroes examine the tent and find that the boy doesn’t live there, just visits. Gerald finds some licorice sticks and takes them.

Carter tells Cole that the men at the zoo work for the Turk whom Bertram was investigating. He’s the most notorious crime boss in the area.

Lee and Carter pay a visit to the Turk. He denies any knowledge of the crime.

Carter catches Gerald chewing on a licorice stick. He takes them for evidence. Gerald says he hasn’t seen that brand since they were kids. Carter knows where the kid is staying.

Carter and Gerald bring Lee to the boys’ home where they grew up. They call the woman who runs it Grandma. They ask her about the painting and she says the artist is Isaiah, but he hasn’t been around for a few days. Gerald knows a hiding space in the house. He finds Isaiah in the cupboard in the washroom.

Isaiah is scared. He claims he didn’t see anything. Carter tells him about all the trouble he used to get into. Grandma convinced him to extend his protective nature and become a cop. It saved his life. Isaiah tells him the truth.

Carter has the Turk pulled in for questioning. His lawyer has five witnesses willing to testify that he was at his restaurant the night Bertram was killed. The lawyer marks Isaiah as a criminal and incredible witness. The DA lets him go and heatedly scolds Carter and Lee for bringing him in with no real evidence. Cole takes responsibility.

Lee finds that one of Bertram’s case files on the Turk is missing fingerprint evidence. They decide to visit his paralegal again.

Didi watches Isaiah at the station. He recognizes the DA as one of the men who murdered Bertram and excuses himself to the bathroom. The DA follows him, but Isaiah escapes through a window. The DA gets his address for evidence.

Bertram’s paralegal gives Carter an older copy of the case file. This one has fingerprints and additional financial records. She tells them only one person had access to the file in between – the DA.

The Turk goes to Grandma’s house posing as Social Services. She tells him Isaiah won’t be home for a few hours. He searches the house and sneaks in his cronies.

Carter and Lee sneak in through an unlocked window. The Turk opens the washroom cupboard, but Gerald is waiting for him. He tells Isaiah to run. He was hiding in the dryer. With amazing martial feats, Lee beats up the Turk’s men. Carter saves Grandma, who saves him in return. She bashes a mobster in the head with a kettle.

Credit: Richard Cartwright/CBS ©2015 CBS Broadcasting, Inc. All Rights Reserved

Isaiah hot-wires the car out front, but the Turk’s men shoot up the vehicle. Isaiah dives behind it. Lee takes out the men, but the Turk comes outside with his gun drawn. Carter shoots him. Isaiah is okay.

The DA is called to the police precinct. Captain Cole handcuffs him.

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