Cassandra Linfield is a lady fossil collector who declares she will never marry as no man will ever take her studies seriously. When circumstances force her to travel to Town for the Season, Cassy infiltrates the hallowed portals of the Geological Society from which she has been banned. She is horrified when she comes face to face with her nemesis, the infuriating Earl of Rothbury.

Lord Rothbury is a gentleman-geologist with a turbulent romantic past. After a youthful disappointment he vows never to fall in love again, and makes the decision, instead, to seek out a convenient wife when he returns to England from his geological travels abroad.

Brought together by their close family ties, Cassy and Rothbury collaborate on a geological paper and discover a powerful attraction. Marriage, however, is the one subject they cannot agree upon. But when Cassy's life is threatened, the two realize that love matters more than their objections.