The Arctic Patrol Mystery (Hardy Boys, No. 48)

Private investigator Fenton Hardy enlists the aid of his teenage detective sons in a search for a missing man being sought by an insurance company. All leads to the sailors whereabouts have petered out and the boys fly to Iceland, the mans native land, hoping to find a new clue. From the moment Frank and Joe arrive in Reykjavik, the capital city of Iceland, they are in constant danger. In the spine-chilling pursuit that follows, Frank and Joe uncover a diabolical espionage plot that threatens the life of a U.S. astronaut and NASAS moon project.