This book has all the ingredients a thriller should have. We have a futuristic theme-park with a bunch of terrorists threatening to kill people if their demands aren't met and any move to try to warn the customers or try to determine how the terrorists have infiltrated the computer systems, will result in many customer deaths.

In the theme park called Utopia, holographic technology and realistic historical depictions are the norm with robots performing maintenance and in some instances, serving the clients. Something seems to cause the robots to malfunction (I just remember the line "Welcome to Westworld, where nothing can go wrong, go wrong, go wrong..."). The robot's programmer is called in to deprogram and remove the robots. What he finds is that instead of accidental system problems, someone has planted a "Trojan horse" program that causes the malfunctions.

Meanwhile, the park's management is approached by a terrorist, to give the master program of the park's core program, or a lot of people will die. We later find that this program could be used by the military to defeat heat seeking missiles and other programmed armaments. Therefore, giving up the code could have world-wide ramifications.

The story progresses to an exciting conclusion. The only issue I had that prevented me from giving it 5 stars, is people are getting hurt and killed on the attractions and the park officials are able to keep it quiet from law enforcement. I you can overlook this, then it should be a perfect thriller.