Allie Lake is a scientist is on a held-up flight travelling home from a job when she is seated next to troubled movie star Milo Ford. She is in no mood to talk to him, whoever he might be. Her most recent project at a research station has just come to an end and she's about to move in with her sister and her love life is non-existent. As for Milo, he wants nothing more than to be at home hiding out with a little normality. Instead, he has to go and film a movie in the Romanian mountains... all the while, the press are getting closer, circling his most closely guarded secret. Post-flight, they both quickly realise they've accidentally swapped phones with their fellow passenger. Easily rectified, except Milo's about to be on a remote set for a month... and Allie has no idea who Milo is, only that he is the keeper of her entire digital life. As they trade back and forth on each other's phones, they can't help but notice there's more to their chat than practicalities...