00990    a2200193   4500001000700000020001800007020000900025041000800034082001000042245003500052246002600087490003500113520051400148856002400662040002500686260003700711300001700748700003100765118602  a9780448089157  qenc.  aeng  a[Fic]10aThe Hardy boys mystery stories  aThe sinister signpost  aThe Hardy boys mystery stories  aIn one of the most dangerous and intriguing cases of their careers, Frank and Joe Hardy help their father investigate a series of mysterious car accidents. Each of the drivers had seen a signpost marked DANGER shortly before his accident. The young detectives investigate, only to discover that the signposts have vanished. The attempted theft of a secret experimental motor and the kidnapping of a famous race horse are part of this thrilling case, which proves to be as sinister as the signposts themselves.  u000031/00003159.jpg  aBR-BrIDEAcBR-BrIDEA  aNew YorkbGrosset & Dunlapc1996  a180 p.bill.  aDixon, Franklin W.eauthor