Natasha Tzetcovich, a teenage violinist goes missing from a concert hall before a big show. The mess in her dressing room suggests she has been abducted after a struggle, and this theory gains weight when the team discover she has recently been stalked by a fan with an unusual obsession with her. However, the girls' violin is also taken and the agents learn that it is worth half a million dollars. Martin goes undercover in order to track down the violin, and when he finally does, more shady characters appear as suspects. Upon investigating the girl's parents, the team discover that the stepfather has a criminal past and that certain old enemies may be in New York. However, when information is provided by the missing girl's boyfriend, the teenage son of her manager, it becomes obvious that the girl is desperately unhappy with her life and may have been looking for a way out, and when Vivian finds drugs in her bedroom, it seems that anything is possible. When the shocking identity of the stalker is revealed the team realise they must find him in order to find the missing girl.