There is a plot in "1408 Phantom Room" that I don't understand. Can anyone explain it to me?

Plot summary of "1408 Phantom Room":

The protagonist Mike Anselin (played by John Cusack) is a horror novelist. Mike, who takes it as his job to pretend to be gods and ghosts, is actually a complete atheist on weekdays. In order to complete his new book, Mike decided to find a "haunted" room to stay for ten days, and he was brave enough to finally choose Room 1408 of the Dolphin Hotel, which was rumored to be the spookiest.

The hotel manager Gerald Olin (played by Samuel L. Jackson) took out photos of dozens of bizarre deaths in that room over the years to persuade Mike not to take risks, but Mike Don't care, stick to your choice. After moving into Room 1408, a series of bizarre supernatural phenomena made Mike completely change his outlook on life. A large number of real-life experiences of horror and horror have really accumulated material for Mike's new book, but the key to the problem is that he must get out of that room alive first.

Extended information:

Cast:

1. John Cusack plays Michael Enslin (MikeEnslin);

2 , Samuel L. Jackson plays Manager Olin (Gerald Olin);

3. Mary McCormack plays Lily Enslin;

4. Jesse Smith ·Jessica Anthony plays Katie Enslin;

5. Tony Shalhoub plays Sam Farrell;

6. Len Cariou plays Michael’s father ;

7. Isiah Whitlock Jr. plays HotelEngineer;

8. Kim Thomson plays HotelDeskClerk;

9. Binny Yoo Quadez plays Claw Hammer Maniac;

10. Andrew-Lee Potts plays Mailbox Gu.