Who Do You Think You Are?

Who Do You Think You Are?
8/7c NBC
History, travel, real-world drama and celeb profiles all intertwine when stars explore their family trees in this seven-part series co-executive produced by Lisa Kudrow. Adapted from a British documentary series, the show begins its ancestral odysseys with first subject Sarah Jessica Parker. The Emmy-winning Sex and the City actress charts her lineage in a journey of self-discovery that directs her to Northern California and then Salem, Mass. — Dean Maurer

Ghost Whisperer
8/7c CBS
The series reaches its milestone 100th episode, which is directed by series star Jennifer Love Hewitt. It begins when Melinda meets a ghost who tells her about a secret munitions dump containing unexploded bombs. The ghost further reveals that one of the bombs is missing...and that someone will die as a result. — Bill Ecklund

Numb3rs
10/9c CBS
In the penultimate episode of the season (and perhaps the series), Don investigates two deaths that are connected to sexual assaults that were committed many years earlier. The probe reveals the victims were raped by one of their former teachers when they were kids. On a much happier note, Charlie and Amita receive a terrific job opportunity in London, but it could force them to alter their wedding plans. — Tim Holland

Caprica
9/8c Syfy
Since the protagonists and their basic motivations have been established, the time seems right to add new, pivotal players to the mix. John Pyper-Ferguson, who appeared in a few episodes of Battlestar Galactica, clocks in as a rival industrialist with a tempting offer for Daniel while James Marsters (Spike to Buffy fans and Brainiac to Smallville folks) turns up as a foil for Sister Clarice. — Michael Chant

Dog Whisperer
9/8c National Geographic
Some misunderstood breeds, like Pomeranians, German shepherds and pit bulls, get a bad rap. But the truth is, when raised responsibly, all are capable of being perfect canine companions, as evidenced over the years by Cesar's beloved pit bull, Daddy, who sadly succumbed to old age last month. In this installment, the host counts down the most aggressive breeds, as voted on by more than 10,000 viewers, and revisits some of his toughest cases to dispel some myths about aggression. — Karen Andzejewicz