On Halloween, Doctor Strange comes to Iron Man, Hulk, and Thor for help when Mindless Ones and winged demons from the Dark Dimension appear on Earth. When Dormammu briefly appears near Stark Industries' Arc Reactor, he manages to steal the Eye of Agamotto from Doctor Strange. Now Iron Man and Doctor Strange must put aside their differences in science and magic in order to reclaim the Eye of Agamotto and defeat Dormammu before he makes plans to conquer Earth and other dimensions.
- Hawkeye,Captain America,Black Widow and Falcon do not appear in this episode.
Appearing in "Into the Dark Dimension"
- Iron Man (Tony Stark)
- Hulk (Bruce Banner)
- Dr. Stephen Strange
- Mindless Ones
- Captain Marvel (Carol Danvers) (Mentioned)
- Mangog (Mentioned)
- Midgard Serpent (Mentioned)