Rohrenbacher was last seen on March 18, 1994 in Los Angeles County, California. He went on a hike in the San Gabriel mountains and never returned. He was not reported missing for a week. His car was discovered abandoned off Highway 39 between Pigeon Ridge and Valley of the Moon, near San Gabriel Canyon Road, shortly afterwards. There were no footprints around the vehicle, but two storms that occurred prior to the car's discovery would have washed away any tracks that had been there.

Rohrenbacher left behind his two dogs, whom he was very attached to. He also left meat defrosting in his kitchen sink. An extensive search of the San Gabriel mountains turned up no sign of him and his case remains unsolved.