Hmmm just like in Untraceable, the writing itself was good, and this one seemed tighter BUT the heroine wins the award for the most TSTL Fiction FBI Agent EVER.
I don't even know where to begin (and I guess I"ve seen too much Criminal Minds) ...things that were implied should have been said and vice versa, when a serial killer calls your hotel room, don't roll over and go to sleep, get the call traced, when a woman tells you a cop in San Marcos has a lead for you and you're IN San Marcos, stop and call him before you leave town--REALLY?? ARE YOU FREAKING KIDDING ME?!?!? REALLY???? There were more but you get the picture.
On a scale of 1 - 5 for me not guessing who the murderer was and the ingenious use of geocaching, I give a 5. For another slightly scattered story and FBI agents who didn't really feel like FBI agents as well as the aforementioned TSTL heroine, I give a 1.