The Ghostly Gondolier appears in "A Menace in Venice", an episode of The Scooby-Doo Show. He was the disguise of Mario, who sought to steal a set of medallions that would grant him access to an ancient treasure.
According to legend, the Ghostly Gondolier was the ghost of a traitor who had cursed a ruler of Venice and all of his descendants.
He was a humanoid ghost with black eyes and yellow sclerae. His mouth also glowed yellow, but his face cannot be seen. He wore an indigo tunic with a grey cloak, and knee-high grey boots, with a matching grey belt.
When Mystery Inc. visited their friend Antonio in Venice, they ran afoul of the Ghostly Gondolier in his medallion-stealing scheme. When Daphne Blake tried on the third medallion at the museum, the Gondolier simply kidnapped her to get the medallion and used his deflatable rubber gondola to escape. He then kidnapped Antonio to get the fourth and final medallion.
The Gondolier attacked the gang one last time. This, however, led Scooby-Doo to discover the ghost's hideout. After the prisoners were released, Velma Dinkley realized that the Gondolier would be going to the Plaza de San Marcos, as depicted in the picture. They caught up with him as he found the treasure, and he was captured at the end of a long chase. The Ghostly Gondolier was unmasked to reveal Mario.