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
Dracula arrives in England and starts feeding on Lucy Westenra.
Act II
Dr. Seward and Van Helsing give her blood transfusions, but she turns into a vampire anyway. They kill her and start laying plans to kill Dracula as well.
Act III
Dracula attacks Mina Harker. Things are looking desperate. The novel wraps up with Dr. Seward, Van Helsing, and crew pursuing Dracula to the gates of Castle Dracula, where they finally kill him.