The Hardys found their friends on the tennis courts of Bayport High.

“Hi, fellows!” called Chet Morton when he saw

Frank and Joe approaching. “You’re too late for a game. Where’ve you been?”

“We had something important to do,” Frank replied. “Say, we need your help.”

“What’s the matter?” asked Tony Prito.

“Oscar Smuff is trying to win that thousand-dollar reward and get himself on the Bayport police force by interfering in one of Dad’s cases,” Frank explained. “We can’t tell you much more than that. But the main thing is, we want to keep him from catching the six-o’clock plane. We-er- don’t want him to go until seven.”

“What do you want us to do?” Bill Hooper asked.

“Help us figure out how to keep Smuff in Bay-port until seven o’clock.”

“Without having Chief Collig lock us up?” Jerry Gilroy put in. “Are you serious about this, Frank?”

“Absolutely. If Smuff gets to a certain place before Dad can, the case will be ruined. And I don’t mind telling you that it has something to do with Slim Robinson.”