AllMovie

Invisible Informer serves as a feature-length vehicle for Republic serial queen Linda Stirling. The story is set in motion by a missing necklace, worth $100,000. The insurance agency covering the necklace suspects that the "theft" is a fraud, and dispatches special operatives Eve Murray (Stirling) and Mike Reagan (William Henry) to get to the truth. In the course of their investigation, Eve and Mike must contend with several murders, perpetrated by the thief with the help of a nasty police dog. Usually seen battling burly bad guys or escaping deadly perils in her other films, Linda Stirling is afforded a few steamy love scenes in this one, which she pulls off with elan.