Doctor Doom's reign of terror is just beginning. Here's what to know about his role in the upcoming movie, 'Avengers: Doomsday,' including cast, release date and potential plot.

This story discusses major plot developments, including the ending and post-credits scenes, in "The Fantastic Four: First Steps," currently playing in theaters. From the very first scene, the question of what will become of the child of Reed Richards (Pedro Pascal) and Sue Storm (Vanessa Kirby) looms over "The Fantastic Four: First Steps.