The tranquilizer Marcia took in the dispensary of the space lab where she worked seemed harmless enough. But it didn't calm her down; instead, it thrust her headlong into danger - prey to a network of ruthless spies. For one of the "harmless" capsules in the bottle Marcia used contained microfilmed secrets worth millions to unscrupulous agents. The only way for them to get that pill was to mark Marcia for murder!