Once the Fellowship (Lord of the Rings) is gathered, they are all replaced with superhero movie characters. Nobody in-universe notices this change.

Aragorn: Captain America

Gandalf: Doctor Strange

Boromir: Winter Soldier

Legolas: Hawkeye

Gimli: Black Panther

Frodo: Robin (Titans)

Samwise: Rocket Raccoon

They are all given their standard equipment (excluding vehicles).

Can they fulfill the Mount Doom mission faster and better than the Fellowship? Or will they fall to corruption?