The Avengers are visited by four mysterious children, they are powerful and angry. Thor cannot believe his eyes, they go by many names, Jormungandr or Hiccup Haddock, Fenrir or Jack Frost, Hel or Rapunzel, Sleipnir or Merida...they have come to find their father and help destroy the evil Thanos who had tormented their father. Will the Avengers join the big four or imprison them?