Danger on Vampire Trail by Franklin W. Dixon

introduced himself as Edward K. Mungo.
    â€œPretty efficient layout you boys have here,” he said.
    â€œWe like it,” Frank replied.
    â€œWhat’s your name?” the man asked.
    â€œI’m Frank. The chef is Chet. The guy fishing is Biff. And the other one is Joe.”
    Chet, meanwhile, continued his stint at the stove, cutting up three large onions into a skillet with melted butter.
    Frank said, “Mr. Mungo likes the smell of our chow. What do you say we invite him to dinner?”
    Chet nodded and the man said, “That’s very friendly of you. Thank you. I accept with pleasure.”
    When the meal was over, Mungo said, “It’s a lucky thing you fellows parked near me. How would you like to help me launch my cruiser?”
    â€œGlad to,” Frank said.
    The hitch was uncoupled and the boys trundled the cruiser into the reservoir. Mungo started the motor, waved, and set out with a throaty purr of the engine.
    Darkness was falling but not fast enough to conceal another boat coming up to meet the cruiser. Both craft stopped, with motors idling.
    â€œI’d like to take a look at what’s going on out there,” Frank said.
    â€œWe’ve got our foldboat,” Biff remarked. “Let’s put it together.”
    The two-seater collapsible boat was pulled out of the trunk of their car and quickly inflated. Frank and Joe got in and paddled silently across the dark waters.
    They came as close as they dared to the two boats. The sounds of voices drifted over the lake, but the conversation was not clear enough to be understandable. Suddenly the conversation ceased. A powerful flashlight illuminated the area. Frank and Joe ducked and began to paddle back toward land. When they reached the shore, Biff and Chet were waiting.
    â€œQuick, put the boat away,” Frank said.
    He and Joe stood on the shore while the others deflated the boat and stowed it. They waited a long time but the cruiser did not reappear.
    â€œHe’ll have to come back some time,” Frank said. “Well, let’s hit the sack. We can check that guy out in the morning.”
    The four slept soundly. At daybreak they rose, dressed, and stepped out onto the dewy grass to see whether the boat had returned.
    â€œHe came back all right,” Chet said, pointing to a cruiser drifting at anchor a few feet from shore. “Mungo’s probably sleeping aboard.”
    â€œWhy not blow the whistle on him right now, Frank?” Biff asked.
    â€œNot so fast,” Frank replied. “Take a look at that boat again.”
    The boys peered through the mist rising over the reservoir. Biff exclaimed, “It’s not the same one!”
    â€œCorrect,” Frank stated. “Mungo pulled a switch during the night!”

CHAPTER VIII
    The Missing Cruiser
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    THEIR evidence against the Magnacard swindlers had vanished! The boat lying at anchor in the still waters of the reservoir was not the one they had trailed along the highway.
    â€œWhat’ll we do now?” Chet asked.
    â€œPlay it cool,” Frank replied. “Mungo’s probably sleeping out there. If we act suspiciously, he might give us the slip.”
    It was decided that he and Joe would take the rubber boat and scout the reservoir. If they had any important news for Chet and Biff, who were to keep an eye on Mungo, they would report it over their two-way radio.
    Just then the boat they were watching rocked a little, sending a small ripple over the quiet surface.
    â€œLet’s duck,” Joe suggested. “Mungo’s probably getting up.”
    Frank carried the foam boat some distance down the shore, while Joe lugged the small motor. When they were safely out of Mungo’s earshot, they unlimbered the boat, attached the motor, and cruised along the shore, keeping a sharp lookout for the white craft.
    The sun grew hot, dispelling the mist over the reservoir. Along the shore were more