Cassie and Tom lost their parents at a young age and relied on each other--as well as a community of friends--to get through it. Especially Tom's best friend, Sam, who always made sure Tom and Cassie were surrounded with love. But now, twenty years later, Cassie has lost Tom as well. Then she finds an envelope with her name on it, written in Tom's terrible handwriting, and she knows immediately what it is. It's the first clue in the Christmas scavenger hunt Tom made for her every year; he'd promised her for months that this year's would be the grandest one yet. Tom's clues set Cassie on a heart-wrenching and beautiful journey that will change her life-if she lets them. And as she travels from London to the Welsh mountains to the French countryside, she reconnects with old friends, rekindles a lost love, and most importantly, rediscovers herself. But once she's solved the final clue, will she be brave enough to accept the gift her brother has given her--and the love it's led her to?