Jason Lewis, the “Sex and the City” stud, has been cast as the lead of a new TV pilot, “Rio!” Lewis will play an international detective who goes to Brazil to investigate a crime, and decides to stay after he falls in love with the city and its music, beaches and nightlife. Filming on the show, part “Miami Vice” and “Magnum, P.I.,” starts next month in Rio. It was created by Scott Steindorff, an executive producer of “Las Vegas” and HBO’s “Empire Falls.”