Desperate to avoid the endless parade of “I dos” alone, Rachel and Cam make a pact—be each other’s plus one for the season’s weddings. The rules are simple: don’t overcomplicate things, be there for each other, and—most importantly—don’t fall in love.

Stella Jayne Walsh, New York City’s top-rated trauma surgeon has never lost a patient—until the day she does. Her world shatters, and she’s swept into an adventure that launches her from Manhattan into alien worlds in the far reaches of space.