I am sure you can read all the other reviews to get your spoilers, but I don't like to do that. So... The movie takes place during the time John is still trying to deal with the news of his impending death, and going through treatment options of his cancer. Finding a "common soul" in his support group, who shows "miracle" signs of conquering his cancer, John seeks out the same solution. The "miracle" could be to good to be true, and as the movie progresses, John and Amanda may have underestimated the group they are currently testing, to the possible death of John in his own trap.
