King Arthur! is a magazine story.
The Fat Controller chooses Arthur to deliver costumes to the castle for the special medieval open day. Emily was taking passengers to the castle and together Arthur and Emily watch the fun.
That night, Arthur dreamt that the shed was a castle. Next morning, he tells his dream to Emily who has an idea which she tells to the Fat Controller.
A week later, something special arrived from the works for Arthur - a cardboard crown! Meanwhile, a truck cover was draped over Emily's boiler and it looked just like a fine cloak. After the other engines had finished work, they all lined up in the yard where Lady Hatt had made lots of refreshments. The Fat Controller then read out an old story about engines, and Emily calls it "King Arthur and his Engines of the Turntable". Arthur then rotated slowly on the turntable so that everyone could admire his magnificent crown.
- In the 2011 version, an exclamation mark was added to the title.
- The title maybe a reference to King Authur; An actual king who once lead Briton in the 5th and 6th centurey.