I was not familiar with the story of Donald Crowhurst before I saw this movie. He was a dreamer with an adventurous spirit. I thought this movie might be similar to Kon Tiki but it was very different. Not so much an adventurous survival story, it was more psychological. This guy got himself in between a rock and a hard place. No spoilers. I rated it a 7, I love Colin Firth in pretty much everything and Rachel Weisz was terrific too.
