Nancy goes on a long, strange trip as Weeds celebrates its fourth year. After Mary-Louise Parker's drug-dealing mom burns down the Agrestic rental, the Botwin clan flees to Bubbie's beach house, near Tijuana, where they reluctantly join forces with Nancy's cranky father-in-law, Lenny (Albert Brooks). While Celia (Elizabeth Perkins) does time for renting out a grow house, Nancy cozies up to a Mexican drug cartel. With nowhere else to go, Doug (Kevin Nealon) joins Nancy, Andy (Justin Kirk), Silas (Hunter Parrish), and Shane (Alexander Gould) in Ren Mar.

Sometimes change is a good thing, sometimes not. As creator Jenji Kohan explains in her commentary, "The writers were getting kind of restless." Adds writer Roberto Benabib: "We were done with suburbia." Fortunately, the new location adds interest, and Brooks makes for an inspired (albeit brief) addition, but Celia's punishment--humiliation, beating, pistol whipping--for selling out Nancy goes on too long. (The original theme song and opening credits also disappear after the premiere.) When a cigar-chomping politico (Demián Bichir) and an attractive divorcée (Julie Bowen) with an eye for 17-year-old Silas enter the picture, events take a darker, sexier turn. Even 13-year-old Shane, who longs to join the family business, acquires a couple of groupies.

As in previous years, the season ends with a cliffhanger, but in light of the insurmountable scrapes she's got herself into before, Nancy seems likely to emerge unscathed in year five when Jennifer Jason Leigh joins the show. If comedy takes a backseat to drama this time around, Weeds remains compulsively, addictively watchable. Bonus features include seven cast and crew commentaries--Parker and Gould are the only key players missing--and eight featurettes, including a tour of Bubbie's tchotchke-filled abode and a look at the Drug Enforcement Agency, which plays a regular part in the program. --Kathleen C. Fennessy