A young architect has often told about the debt he owes to a fellow ex-GI whom he has never met but who saved his life after he was wounded in Vietnam. The architect is delighted when his lifesaver shows up unexpectedly on the night of his birthday party. But it soon becomes apparent that the visitor is a hopeless nerd with no social sense, little intelligence and less tact. Overstaying his welcome leads to one uproarious incident after another until a surprise ending.