For a three-act plot analysis, put on your screenwriter’s hat. Moviemakers know the formula well: at the end of Act One, the main character is drawn in completely to a conflict. During Act Two, she is farthest away from her goals. At the end of Act Three, the story is resolved.
Act I
With the guidance of Evangelist, Christian leaves the City of the Destruction.
Act II
Accompanied in turn by Faithful and Hopeful, Christian encounters strangers and challenges on his way to the Celestial City.
Act III
Christian and Faithful reach the gates of the Celestial City and are admitted into it.