Tic-tac-terror (The Hardy Boys #74) -

Franklin W. Dixon

Wanderer Books / Pocket Books

1982

201 páginas

6h 42m

ISBN-13: 9780671423568

Tic-Tac-Terror is the 74th title of the Hardy Boys Mystery Stories, written by Franklin W. Dixon.
It was published by Wanderer Books in 1982: Frank and Joe Hardy are asked to investigate a mystery involving a world-famous spy from HAVOC, an international network of terrorists, who wants to defect to the U.S. Frank and Joe know the spy as "Igor”.

Also a million-dollar emerald from South America has vanished. Joe and Frank think “Igor” was involved. Their only clue is mysterious symbol in shape of tic-tac-toe. The game lead to a building that is run by the U.S. government. The building has a bomb and the Hardys are trapped in a deadly game of tic-tac-toe.
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https://en.wikipedia.org/wiki/Tic-Tac-Terror
https://series-books.blogspot.com/2016/04/hardy-boys-74-tic-tac-terror-75-trapped.html
'(...) In Hardy Boys #74, Tic-Tac-Terror, Frank and Joe search for a missing man who disappeared on the way back from South America. Soon, the boys learn that the man's disappearance is tied to a missing emerald and a dangerous spy organization that threatens national security'...'