“A Stranger Among Us” sets a love story - or half a love story - in the midst of a murder investigation, and both elements are mishandled. The love story isn't even supposed to get us steamed up, and anyone familiar with good crime fiction will find the mystery part of the story hopelessly shallow and childish; the solution would not strain Nancy Drew. The film stars Melanie Griffith as a New York detective with a reputation for acting first and asking questions later. Assigned to investigate a disappearance connected to a jewel robbery, she finds herself in the middle of a closely kni...