The plot you've outlined reminds me of Sphere, a 1998 Sci-Fi psychological thriller film adapted from a Michael Chrichton novel — although they don't return "home", they return back to their underwater habitat.
In the middle of the southern Pacific Ocean, a thousand feet below the surface, what is believed to be an alien spacecraft is discovered after a ship laying transoceanic cable has its cable cut and the United States Navy investigates the cause. The thickness of coral growth on the spaceship suggests that it has been there for almost 300 years. A team made up of marine biologist Dr. Beth Halperin (Sharon Stone), mathematician Dr. Harry Adams (Samuel L. Jackson), astrophysicist Dr. Ted Fielding (Liev Schreiber), psychologist Dr. Norman Goodman (Dustin Hoffman), and U.S. Navy Capt. Harold Barnes (Peter Coyote) are tasked with investigating the spaceship. The team (along with two navy technicians) are housed in a state-of-the-art underwater living environment called the Habitat during their stay on the ocean floor.
Eventually, only Harry, Norman, and Beth remain. At this point, they realize that they have all entered the world of the perfect sphere. The Sphere has given them the power to manifest their thoughts into reality. As such, all of the disasters that had been plaguing them are the result of manifestations of the worst parts of their own minds.
EDIT It's been a while since I saw the film so I didn't want to confirm the last part of your question, as I thought I remembered an unfinished book but was unsure… this TV Tropes article confirms:
This happened with Twenty Thousand Leagues Under the Sea in the film version of Sphere. It wasn't completely blank, but just stopped where the reader was too scared to read past that page while he was a child.