He is very caring, sweet, thoughtful, but sometimes absent minded. He's the kind of person that will never give up until he gets down to the bottom of things, like trying to find out that Bella was a mermaid. He has a passion for diving and collecting shells from the bottom of the ocean.
Will is a skilled free-diver who loves spending time in the ocean and can dive well over 50 meters. While diving near Mako Island, he finds his way into the Moon Pool just as a water tentacle suddenly appears in front of him, it looked so real that he touched it and it knocked him out cold. After then, he continually tries to find the source of the occurrence, despite the fact that the mermaids tell him he had slipped and hit his head, and possibly had a weird dream. Will noticed that nothing adds up about Bella and figures out she's a mermaid. Will attends the same school as Cleo, Rikki, Bella and Lewis, and lives in a old boathouse, on the edge of a canal, because his parents wanted him to have his own space. Will also has an elder sister named Sophie, who has a very bad influence on him, and is very pushy about his diving training, only because she wants to make use of his diving skills to make fortune and fame. Bella helped Will realize that he didn't dive for Sophie, but he dives for himself. He eventually finds out about Bella's secret, but he keeps Cleo and Rikki's identities safe. But after he finds out that Cleo and Rikki are mermaids as well, he wholeheartedly agrees to keep it secret from the rest of the world. When Lewis leaves for America, Will replaces his role in protecting the girls.
See the main article: Will-Bella Relationship
Will develops a crush on Bella almost as soon as she comes to town. Over short time, they become very close friends, but Bella gets torn between friendship and love when Will's obsession with Mako Island puts their relationship in jeopardy. He eventually discovers Bella's secret, and becomes more interested in her tail than Bella herself and drives her away. Later he finds out Cleo and Rikki are mermaids, but decides to keep it safe. They retain a close friendship until the episode "Beach Party", where he practices with Rikki to ask Bella to a beach party, but Bella overhears their practice and mistakes him for taking Rikki to the party, and asks Nate instead. Will, persuaded by his sister, decides to go with Rikki. At the party, he admits his true feelings to Bella and they kiss and become a real couple.
Rikki is Will's closest platonic friend. In the episode "Mermaid Magic", Will is saved by Rikki after he free dives too deep and too fast. Afterward they grow closer. When Cleo and Bella visit him at home he is more interested to see Rikki. In the episode "Beach Party" Will and Rikki are seen hanging out one on one together regularly. At the beginning of the episode they are lounging around his boat house talking about their romantic situations. Another time they are fixing a motor together. Her tomboy personality makes him considers her one of the guys. He can tell her stuff he can't tell other people.
- Will is like Max Hamilton, because he made the necklaces for Rikki and Cleo, like Max made the lockets.
- Even when Sophie obviously does something rude or sneaky, Will still stands up for her.
- He has never stayed anywhere long enough to make many friends.
- He was home schooled before starting at school with the others.
- Luke Mitchell states that he was very nearly made a merman for a dream sequence.
- Main article: Will Benjamin/Gallery