"New Best Friend" is a slow, pulpy but compelling mystery-thriller. It works in large part thanks to Meredith Monroe, who brings real depth to her role. Another one of its strong points is that the characters are not clearly labeled as "good" or "bad"; you can feel the evil hanging over everything but you never know where it will come from. On the negative side, there is at least one gaping story hole (in a flashback near the end, Kirshner's character appears to be at two different places at the same time!), and Taye Diggs is miscast (too young) as the investigator on the case. (**1/2)