Charlie Contour and Holly Hamilton were stars of a detective series in the ’90s, but their lives have taken different paths since the show ended. Charlie is a suburban housewife and mother, but Holly longs to return to her glory days as a TV star. That’s about to change when a megafan, Nick, witnesses a crime. He refuses to speak of it to anyone but his favorite TV detectives, prompting the former gal pals to reunite to solve a real mystery. The show’s plot is a case of art imitating life as “Mystery Girls” reunites “Beverly Hills, 90210” co-stars Jennie Garth and Tori Spelling as the lead characters.