Sorry to bother, but you sent a invalid question, we don't know how to answer this unless you state what we are writing on.
The subordinate clause is "you must start researching now"
Of great value; not to be wasted or treated carelessly.
Why did the neighbours immediately call the cops? Did they already know he was guilty? Were the cops making him go insane at the end? Did the cops suspect him before he admitted it? What is wrong with the narrator mentally? Is he even human?