Brandi comes home after spending the night out at a rave, but Dottie thinks she's spent the night studying. Suddenly DEA agents burst into the house and arrest Brandi at gunpoint on the charge of drug-dealing. Downtown, Agent Forrest confronts Brandi and her attorney with 20 hits of ecstasy she had in her possession plus photos of her making the buy. Brandi tells the agent she was working on trying to find a skip. Forrest tells her that a girl named Georgia OD'ed at the rave and that Brandi could possibly be looking at murder charges.
Ricky puts up the bail for Brandi. Dottie is upset with her daughter for not telling her about this case, but Brandi counters that the nature of her undercover work made it necessary to work alone. She bought the ecstasy from a dealer to establish credibility. Georgia was a friend of hers. She was looking for Dickie Ramos, a big-time supplier of the drug. At home, Farrell puts an ankle-bracelet monitoring device on Brandi. He tells her he understands what she did; cops sometimes use and buy drugs in undercover work and it's never talked about or put in reports. The DEA agents come by to say they have found no trace of Alex, the drug dealer Brandi says she bought from, and they suspect he is a phony. Dottie pleads for them to keep searching, and Agent Forrest agrees to do so for 48 hours. She gives the Thorsons the news that Georgia has died. At 3AM while Dottie and Tiny are in bed, the DEA comes back, looking for Brandi. She's gone, the bracelet left on the floor.
Dottie begins to trace Brandi by looking through her possessions for clues to where she might have gone. Tiny argues with her that it is a dangerous risk to their relationship to invade her privacy this way. Dottie tells him forcefully that her daughter has left her no choice. She finds photos of Brandi at other raves, some dating back a couple of years, revealing a life she's kept secret from her mother. Meanwhile, Brandi goes to meet Louis, asking him where some action will be that night and whether she can meet Alex, one of Ramos' bigger dealers. Louis says he will get in touch. Later, Dottie has hacked into Brandi's computer when Louis sends her a message about the location of a rave that night.
Dottie dolls herself up for the party, but her looks and age make her suspicious to the doormen and she can't get in. Inside, Brandi meets with Alex and Zev, another dealer. To convince them she's for real, she has to take a dose of the drug. Soon it begins to take effect and she wanders through the building dazed. Back at Tiny's a discouraged Dottie is actually thinking of calling Detective Farrell to find Brandi. Jason Quinlin, now working for Tiny, says he thinks he can get Dottie into the rave. The two are admitted and Dottie finds Brandi huddled alone in a basement. The DEA raids the party and Dottie manages to barely eluded them with her daughter in tow.
Dottie takes Brandi to the beach, where she regains her senses. The mother and daughter have a heart-to-heart talk about the secrets Brandi has kept. Brandi tells her she still must go after Manos. She goes to see Alex and Zev again. They ask her why her mother was at the party. Brandi tells them she's leaving town and just needs to make one big score, after which they'll never see her again. They take Brandi for a ride, followed by Dottie. They arrive at the hideout of Manos, then pull a gun on Brandi. Alex orders Manos, who appears to be just a manufacturer, to make up a lethal dose for Brandi to take. Outside, Dottie has called Farrell. She bursts in on the scene with a shotgun, and by the time Farrell, Forrest and other DEA agents arrive, the Thorsons have subdued the dealers. Farrell gets charges dropped against Brandi by giving Forrest the collar for the arrests.