‘Law & Order’ episode enlists N.H. firm’s radar device

Two crime scene specialists are racing against time looking for clues that will lead to two women being tortured by a homicidal maniac. They place a special device against a brick wall, detecting a void on the other side — a secret room. Police officers gain access to the previously hidden room and save the women.

That’s the plot of the Nov. 18 episode of NBC’s “Law & Order: Special Victims Unit.” The device they used isn’t a an idea cooked up by the script writer. It’s the SIR-3000 StructureScan System, a ground-penetrating radar device developed by Geophysical Survey Systems Inc. of North Salem.

According to Chris Hawekotte, GSSI’s director of sales and marketing, “Government and law enforcement agencies all over the world are using ground-penetrating radar in forensics and search-and-rescue missions. The producers of the show were clearly interested in a realistic portrayal of the system being used in this type of application.”

To ensure accuracy in how the device is used, Hawekotte said, the show’s producers “asked us to help coach the actors on the operation.”

In fact, GSSI application specialist Ken Corcoran received a walk-on role in the television show as one of the investigators using the device.

GPR devices work similarly to medical MRIs by emitting electromagnetic waves, which are reflected off underground objects or geological layers of different composition. These signals are then extrapolated into data telling users what’s under their feet — or on the other side of a wall.

GSSI is becoming accustomed to the TV lights. The firm’s GPR devices also have been featured on “National Geographic Explorer.”