A history professor dating an immortal, who finds out at the worst moment that his own family has a story too.
Dane Whitman is a human who teaches history at the Natural History Museum in London and is seeing Sersi. He spends the film as the person things are explained to, which is a job somebody has to do in a story with ten immortals in it.
Minor spoiler
After the credits he opens a case containing the Ebony Blade, an heirloom with his family name on it, and a voice off screen asks whether he is ready for it. The voice is Blade. Neither of them has appeared since.