9. Kingo - Eternals
At the start of Eternals' fraught third act, the heroes learn that one of their own, Ikaris (Richard Madden), willingly led their former leader Ajak (Salma Hayek) to her death when she attempted to stop the imminent birth of the Celestial Tiamut, which would in turn cause Earth's destruction.
Ikaris promises that he'll kill every single one of his fellow Eternals if they try to stop Tiamaut's birth, and though most of the heroes ultimately decide to stand up and fight back against him, there is one notable exception.
After Ikaris departs, Kingo (Kumail Nanjiani) tells the rest of the group that he thinks Ikaris is right, but that he also refuses to hurt any of his friends for his beliefs, and so takes his leave.
While many viewers understandably expected Kingo to return in the final battle and help the Eternals fend off Ikaris, it surprisingly never happens, with Kingo sticking to his word and staying out of the fight.
He only re-appears briefly at the very end of the film once Earth has been saved, being lifted into space alongside Sersi (Gemma Chan) and Phastos (Bryan Tyree Henry) for a tense meeting with Arishem (David Kaye).
Considering how predictable it would've been for Kingo to have a change of heart, this was actually a pretty refreshing approach.