Law & Order: Special Victims Unit was the first of several successful spin-offs of producer/creator Dick Wolf's long-running NBC series Law & Order. Rather than follow the established Law & Order formula of focusing on the "nuts and bolts" of tracking down a wide variety of criminals and bringing them to trial, the spin-off series, per its title, zeroed in on a single division of the New York City justice system: the Special Victims Unit, or SVU, which dealt primarily with such sex-based crimes as rape, incest, pedophilia, torture, and serial murder. Also, whereas the original Law & Order was essentially a story-driven series, the personalities of the main characters on Special Victims Unit often dictated the direction of the investigation and the outcome of the case. Christopher Meloni headed the cast as Detective Elliot Stabler, who sustained a calm, soft-spoken veneer on the job, and who fought a losing battle to spare his family the sordid details of his work. In contrast, Detective Olivia Benson (Mariska Hargitay) was volatile and impulsive; a child of rape, she tended to overidentify with the victims of the crimes she investigated and often as not had zero tolerance for the suspects, no matter what the evidence said. The two other principals were carryovers from other series: Richard Belzer repeated his Homicide: Life on the Street characterization of Detective John Munch, who leaned toward the cynical and sarcastic, and who was driven by the paranoia arising from his steadfast belief in vast sociopolitical conspiracies; and Dann Florek was seen as the SVU team's no-nonsense skipper, Captain Donald Cragen, a character he'd played for three seasons on the original Law & Order. Also in the cast were Munch's partners, departmental newcomer Detective Brian Cassidy (Dean Winters) during season one, and flippant, streetwise Detective Odafin "Fin" Tutuola (Ice-T) thereafter; another street-smart cop, Detective Monique Jeffries (Michelle Hurd), who appeared in the first season only; forensic psychiatrist Dr. George Huang (B.D. Wong), a regular from the third season onward; Assistant DA Alexandra Cabot (Stephanie March), who after being placed in the Witness Protection Program was replaced by ADA Casey Novak (Diane Neal); and, on a recurring basis, Ken Briscoe, the son of veteran Law & Order detective Lennie Briscoe -- played by Chris Orbach, the son of veteran Law & Order regular Jerry Orbach. Popularly known as Law & Order: SVU, this series debuted September 20, 1999, on NBC.