Phone Man Seeks the Earwig

In private Bint Uldrich calls himself Phone Man because he had invented a device that lets him transport through the landline phone wires to distant places where he can look out, reach out of the phone, or even emerge from it entirely to thwart bad guys, do good, or simply note and report back about who is where and the current conditions at the end site.
Here Uldrich uses his invention to try to stop a woman using small stolen items that if one is forcibly put into a victim’s left ear gives the person with a special communicator device close to total control of the actions of that otherwise innocent and unwilling person. She seems to be using different people in a scheme to get rich by making herself sole heir to a fortune and then eliminating its current owners. She murders several people after they have served her purposes and then crudely gouges the devices from their heads to protect her secrets. The damage to the victims seen at autopsy leads to the police calling her the Earwig.
Uldrich gets unofficially but actively involved in the case to help his detective friend Moe Lombardo but also to protect his lawyer girlfriend who is professionally involved with rewriting the essential last will to transfer the wealth.
He must deal with new problems when he gets one of the devices shoved in his own ear and must avoid the control messages while he decides whether to risk the only way he can imagine removing that thing without killing himself.