The beginning of season 21 finds the series back where it began, with the Broward Sheriff's Office. First up, the officers chase down a hit and run driver. A long run ends with a ramming, followed by an investigation of the vehicle which uncovers a machete. Next, a known drug area finds a man on a bicycle who tries to flee. A search reveals cocaine on a man who is on probation. Lastly, officers are responding to a call about a suspicious vehicle near a business. The driver begins to flee as officers arrive. An investigation uncovers a bleary-eyed man behind the wheel who claims to be sleeping, yet a bag of white powder gives the officers another idea.

Palm Beach County Sheriff's witness a speeding car in a drug infested area. Having stopped them in a pursuit, the driver angrily exits his vehicle to ask why he was stopped. He jumps back in his car and speeds off beginning a new chase in which a passenger bails out. The female is the drivers boyfriend which is only discovered after a long inquiry. She reveals he has a vial of crack inside the car. Next, a Spokane Police officer is called to a possible domestic call on the street. Looking up and down the road the officers discover a man standing under a tree in which a female is up in the tree. They find out that the woman often climbs the tree when upset with family problems. Then, a Rialto Police officer spots a drug transaction taking place. The men claim they are construction workers headed to purchase supplies, but a bag of crack on the floor has the officer in doubt.