|Affiliations||Max Tennyson (friend)|
|Occupation(s)||Real State Mogul|
|Powers and Abilities|
|Relatives||Edwin GrandSmith (grandson)|
|Voice Actor||Tom Kane|
|First Appearance||They Lurk Below|
Donovan was one of Max Tennyson's friends. When they were younger, Donovan gained a large sum of money. As a result, he decided to travel the world. When he offered Max to travel with him, Max refused, and Donovan supposedly went on his own.
Many years later, Donovan became a billionaire and started a chain of hotels. He invited Max and his grandkids to come to his newest resort underwater. There, Max, Ben and Gwen met Edwin, Donovan's grandson, who he wanted to take over the family business. However he seemed to have missed the point of family and friendship, leaving him and his grandson somewhat distanced from one another. After the alien robotic squid destroy the hotel, Donovan learns to appreciate his Edwin, and they end up on better terms. He then decides to make a hotel on the moon, and asks the Tennysons if they will be one of the first to try it. The Tennysons refuse.
- He bears resemblance to Walter Donovan from Indiana Jones and the Last Crusade.
- Donovan GrandSmith thinks Grandpa was an ordinary plumber (not part of the association) and teases Grandpa quite a bit about it.