What If Sunsets Could Last Forever?

An aloof young woman who unwittingly discovers the love of her life on a mundane train ride suddenly finds herself elderly and grieving the loss of her life companion. In a surprising and inexplicable turn of events, she sheds her age as she disembarks the train that brought her to this life, and, reboarding, she discovers that she's been given another chance to live it. Along a wild ride of déjà vu coupled with new adventures she learns many things about living a fulfilling life.