In the story, an unidentified Smurf is creating a wooden "Smurf Submarine" and Handy Smurf comes by, interested, and asks the Smurf about it. Because the Smurf's method of diving is pulling the plug and filling it with water, it sinks, and after the Smurf is rescued from drowning, Handy Smurf builds him an iron submarine, which he dives into the water with. Then he is chased by Gargamel, who tries to capture him but in the end does not succeed. Papa Smurf decides that the submarine is too dangerous, and tells the unnamed Smurf not to use it anymore. Instead, it gets converted into a swimming pool.