This best-selling novel by Audrey Niffenegger tells the love story of Clare and Henry—which would be so perfect if only Henry didn't have a pesky genetic illness that causes him to travel through time without warning. This causes his wife Clare all kinds of hassles and heartache. The out-of-order love story captures the loss inherent to love as it constantly moves in and out of moments. This sweeping story covers the lives and tragic turns for both characters. It pulls on your heartstrings even as it inspires through romantic notions about feeling like you know someone when you've only just met. (If you love time travel stories, here are the best movies featuring time travel and twists.)