There were several main story arcs that ran through the Marvel comics.
The main story arc is set approximately 6 million years in the future.
Besides the main story arc, various characters are featured heavily in sub-plots.
The episode is also important in the main story arc concerning the cracks in time and space.
There are three main story arcs in the book series which all have primary antagonists for each arc.
The episode sets up the main story arc of the series by introducing the cracks in the universe.
Moffat was inspired by a crack in his son's bedroom wall and developed the idea into the main story arc of the series.
Then it's down to the action, plunging you into one of the two main story arcs.
There are four main story arcs to the film.
The main story arc of the season dealt with the idea that, at times, humanity is a greater danger to itself.