It is 1845, and Hannah Gardner Price dreams of a world infinitely larger than the small Wuaker community where she has lived all 25 years of her life - for, as an amateur astronomer, she secretly hopes to discover a comet and win the King of Denmark's prize for doing so.
Then she meets Isaac Martin, a young black whaler from Azores who, like Hannah herself, has ambitions beyond his station. Drwan to him despite their differences, Hannah agrees to tutor Isaac in the art of navigation. As their shared passion for the stars develops into something deeper, however, Hannah's standing in the community is called into question, and she has to choose: her dreams or her heart.