In River Cardinal

Dewey Becker was contracted by Cardinal Medicine to invent things. He called his first creations Dewboxes, and Cardinal brought him on full time as a technician to maintain them. After a troubled past as a Sergeant Major in Vietnam, he thought the job would carry him softly into retirement...

R-Aspecticyn, an experimental drug, unlocks a dormant part of the human brain suppressed by evolution. It allows one to see what the world actually looks like. Cardinal Medicine started pumping it into their special Operators to send them on exploratory missions in the fourth dimensional Red Runnel. One of these Operators wouldn't report back. Now Cardinal wants him dead, and there's one man perfect for the job-whether he knows it, or not.