Summer of the Sea Serpent: A Merlin Mission

challenges bravely and wisely. He will—”
    Merlin was interrupted by a strange sound from the water below. It sounded like the deep bellow of a foghorn.
    “What was that?” said Jack.
    “Ah, yes, there is one last thing to do,” said Merlin. He raised the sword and pointed it toward the Cove of the Stormy Coast. Like the beam of a giant searchlight, the sword’s light streamed over the black waters.
    Merlin moved the beam back and forth, as if he were looking for something. “Ah,” he said. “There he is.”

    The light revealed the gigantic head of the sea serpent. Its yellow lamp-like eyes shined back at them.
    “He mourns now,” said Merlin, “for he has lost his purpose for being here. ’Tis time we help him home to the waters of Avalon.”
    The magician lifted the sword slightly. The beam made a path to show the monster the passage out of the cove. The giant serpent slid through the water and soon disappeared beneath the waves of the dark summer sea.
    “His mission is done now,” said Annie.
    “Yes, and so is
yours,
my friends,” said Merlin. “You must climb the ladder to your tree house and go home.”
    By the light of the sword, Jack and Annie found their way to the rope ladder and climbed up into the tree house. When they looked out the window, they saw Merlin standing in the glow of the Sword of Light.
    “Bye!” Jack and Annie called.

    The magician raised his arm and spread his fingers in a wave of farewell. Merlin’s gesture stirred something in Jack’s memory, but he wasn’t sure what it was.
    “Let’s go now,” Annie said.
    Jack took the seashell out of his pocket. He pointed to the words
Frog Creek
. “I wish we could go home!” he said.
    “Wait!” said Annie. “Our shoes! We left them on the beach!”
    Too late.
    The wind started to blow.
    The tree house started to spin.
    It spun faster and faster.
    Then everything was still.
    Absolutely still.

    Jack opened his eyes. A warm summer breeze wafted into the tree house. The noon sun shined between the tree leaves. No time at all had passed in Frog Creek.
    “Merlin was the Water Knight,” Jack said.
    “What?” said Annie.
    “When he said good-bye, Merlin gave us the same wave the Water Knight gave us,” said Jack. “Remember?” Jack raised his hand and imitated Merlin’s gesture.
    “You’re right!” Annie laughed. “Why didn’t I think of that? He always helps us get started on our missions.”
    “And now we have three things from him,” said Jack. He put the pale blue shell on the floor next to the Royal Invitation and the yellow autumn leaf. Then he looked at Annie.
    “Home?” he said.
    She nodded.
    They climbed down the rope ladder and started walking barefoot through the damp, leafy woods.
    “I guess we’ll just have to tell Mom we lost our shoes in a time before Camelot,” said Jack.
    “Yeah,” said Annie, “on our way to get the Sword of Light that was stolen by the Ice Wizardof Winter and guarded by a giant sea serpent who served the Lady of the Lake.”
    “Right,” said Jack. “A simple explanation.”
    “You ready to go swimming at the lake now?” asked Annie.
    Jack remembered the thrill of being a seal and zooming through the deep waters. “It won’t be the same without Kathleen and Teddy,” he said. “We won’t be seals.”
    “We can pretend,” said Annie. “Let’s hurry before Mom decides it’s too late to go.”
    They took off running. They ran barefoot through the woods, over sticks and leaves, through the dappled noon light. Then they ran down their street. They were out of breath by the time they reached their yard.
    “Oh, wow!” said Annie. “Look!” She pointed at their porch.
    Sitting in front of the door were their sneakers.
    Jack and Annie climbed the porch and picked up their shoes. As Jack turned his over, fine white sand fell out—and a couple of tiny silver pebbles.
    “Who—how?” he said.
    A seagull screeched overhead. They looked up. The gull screeched again, then flew away and disappeared into the soft summer light.
    Annie shrugged. “A little leftover magic,” she said. Then she called through the screen door, “Mom! We’re ready!”

Once again, details of old stories from Ireland, Wales, Scotland, and England have inspired a Magic Tree House Merlin Mission. While researching
Summer of the Sea Serpent
,
I read about mythical creatures known as
selkies,
who were said to dwell in the inlets and bays of the British Isles. Selkies were “seal