Tuning in: What's On TV this week.

Saturday July 2

Time Warp Trio (NBC, 10:30 a.m.): Joe, Sam, and Fred travel through time to learn about history via a magic book. Buried among the jokes in the animated series are plenty of interesting factoids that will help prompt an interest in history among the 6- to 10-year-old set. The show is sweetly drawn and thoroughly engaging. First stop, Blackbeard's pirate ship.

North and South (BBC America, 7:30 p.m., followed July 3 with parts two and three): Based on the novel by Elizabeth Gaskell, the story is set primarily in industrial mid-19th century England. The genteel Margaret Hale, a clergyman's daughter from the pastoral north country, finds her new life in the south almost unbearable. But as Hale learns to understand the working poor, she finds rapport with one member of the merchant class - the handsome, if unrefined, John Thornton. Love flourishes even in this grim, gray world until it softens many hardened hearts.

Watch the Skies! (TCM, 8-9 p.m.): Just in time for Spielberg's new blockbuster, "War of the Worlds," the documentary features interviews with the director plus George Lucas ("Star Wars"), Ridley Scott ("Alien," "Blade Runner"), and James Cameron ("Aliens," "The Abyss"), all speaking of the sci-fi B-movies that inspired them. Each of the directors is an avid fan of the genre, and it's a kick to hear why.

Monk (USA, 10-11 p.m.): Tony Shalhoub is back as the brilliant ex-homicide detective whose struggle with an anxiety disorder makes his problem-solving all the more fascinating - and amusing. In the fourth season opener, Jason Alexander guest stars as a rival detective who solves a murder a little too quickly.