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
Joel Harrison Knox is sent to live with his father in Skully's Landing, an old estate outside of a small town somewhere outside of New Orleans. He makes friends with a tomboy named Idabel, and everyone around him seems absolutely insane. Joel finds out that his father is actually paralyzed and that it's Randolph who impersonated his father to send for him after his mother died. He hates it in Skully's Landing and wants to get out.
Act II
Idabel and Joel decide to run away, but they stop off at the fair on their way out of town. Idabel falls in love with a circus performer named Miss Wisteria, who is in love, herself, with Joel. While Miss Wisteria and Joel are on the Ferris wheel a huge rainstorm starts and Joel loses Idabel. He thinks he sees Randolph in the crowd, so he hides in an old house from Miss Wisteria.
Act III
After his escape, Joel ends up back at Skully's Landing, sick in bed. Once he is well he finds out that Idabel has left town, and Randolph takes him on an overnight wild goose chase to visit a hermit in an abandoned hotel. It turns out it was a trick to keep him from the house while his aunt visited from the city, so she wouldn't know she'd been fooled. Joel sees a woman beckoning him from Randolph's window, and he just decides to go with it and enters the house.