While at Purdue University on an NROTC scholarship in 1971, Roland Haas was recruited to become a CIA deep clandestine operative. He underwent intensive training to prepare for insertion into hostile areas, including High Altitude Low Opening (HALO) parachuting and weapons instruction. In the course of his first mission (to East and West Germany, Turkey, Iran, Afghanistan, Pakistan, India, Bulgaria, Romania, and Austria), he assassinated several international drug dealers. On his return, he was thrown into an Iranian prison, where he was physically and psychologically tortured. Over the next thirty years, he served the agency on an as-needed basis, engaging in such activities as hunting down and eliminating members of the Red Army Faction and extracting Soviet Spetsnaz officers from East Germany. His cover jobs included being a part owner of an Oakland health club, which brought him into close contact with steroid abuse in professional athletics, drug abuse in general, and the Hell's Angels, whom he believes tried to have him killed. He also served in Germany as site commander for the Conventional Forces in Europe weapons treaty.

His most recent cover was as the deputy director of intelligence in the U.S. Army Reserve Command, which involved him with the Guantanamo detention facility. A true story that pulls no punches, "Enter the Past Tense" also chronicles Haas' descent into, and recovery from, alcoholism that resulted from the stress of this extraordinary life. It is an eye-opening look at the dark, but many would argue necessary, side of intelligence work - and one that readers won't soon forget.