After murdering an immigrant, he convinces his psychiatrist to declare him insane so as not to be put on trial, but a detective will follow his steps to lock him up.
Unfortunately, the premise is flawed. Being declared insane won’t get him off the legal hook. He will still be arrested. tried and convicted. That’s the way it works. All that being declared insane might do is mitigate his sentence. He might get a life sentence instead of the death penalty.