Fenton Q. Harcourt is an obese, skeptical and serious individual, never wanting to fund any research on myth and legends such as Atlantis. He believes Milo's grandfather wasted his potential on his search for the lost city and believes Milo is doing the same. When Milo tries to propose funding an expedition to Atlantis, in order to not let the board of directors be annoyed with Milo's theories about the city, Mr. Harcourt purposely moves the meeting (to a time that’d already passed, no less) without telling Milo to cancel it. He also teases Milo by saying that the museum depends on him, "With winter coming, that boiler's going to need a lot of attention."
In spite of his mean attitude, however, Mr. Harcourt acts reasonably for an experienced businessman: his refusal to fund down an expedition to Atlantis is partly due not wanting to risk wasting money if the city turned out to be just myth. Additionally, Harcourt really believes that Milo has a great potential, but comes to belittle him when Milo refuses to hear him and insists on Atlantis' existence.
Not wanting to bother the board of directors with Milo's wild theories, he moves around the times for Milo's presentation to deliberately make him late and cause the presentation's cancellation. Milo quickly rushes upstairs after getting his messages and ends up pursuing Harcourt outside. Harcourt insists that, "This museum funds scientific expeditions based on facts. Not legends and folklore." then belittles Milo by telling him he's needed at the museum, "With winter coming, that boiler is going to need a lot of attention." reminding him of his employed job as the museum's janitor despite his expertise in cartography and linguistics. Mr. Harcourt tries to leave in his car, but Milo chases him down insisting he has new evidence and that there is a book in Iceland that could tell them how to get to Atlantis. When Mr. Harcourt closes his curtain, Milo jumps on the hood telling him, "I really hoped it wouldn't come to this," and threatened to turn in a letter of resignation if he refused to fund the proposal. Mr. Harcourt's chaufer, Heinz, swerves to get Milo off the hood interrupting him in midsentence but backs up to where Milo fell off when Milo declares, "I'll quit!" Mr. Harcourt opens back up his window curtain and listens unimpressed as Milo states his seriousness, "If you refuse to fund my proposal-" only to have Mr. Harcourt interrupt him, "You'll what? Flush your career down the toliet just like your grandfather?" In reference to Milo's grandfather, Thaddeus, he mockingly makes the kuku sign showing how ridiculous they all thought he was ridiculous. Mr. Harcourt then tells a hurt-felt Milo to give up the Atlantis business telling him, "You have a lot of potential Milo. Don't throw it all away chasing fairy tales." When Milo insists he can prove the existence of Atlantis, Mr. Harcourt finally gives Milo one last act of mockery telling him, "You want to go on an expedition?" he tosses him a nickel tell him, "Here, take a trolley to the Potomac and jump in. Maybe the cold water will clear your head." After this final act, Harcourt rides off in his car, splashing Milo with water, leaving him depressed and dejected.
He doesn't appear for the remainder of the film. This encounter would be the last time the two would ever see each other, as Milo would stay behind in Atlantis after he helped discover it to help the Atlanteans rediscover their culture and reign as the new king after he and the princess, Kida, wed.
- His actor, David Ogden Stiers, would later play Jumba Jookiba in the Lilo & Stitch franchise.
- Being only in the beginning, it's clear Mr. Harcourt's role is to help set the plot, attempt to be the voice of reason, and to help the audience sympathize with Milo.