Predictability and efficiency have marked Delphine DuVert's orderly life as Castle Stewardess in the small European country of Lethersby—until she is tasked by the monarchy to hire a British researcher. Lethersby needs help solving the 100-year-old mystery of their Lost Queen, a young royal who disappeared into the night during World War I.

Delphine's split-second decision to hire Jack Worthington, a doctoral student at the University of Oxford, has long-lasting consequences when he steps in to protect her from an angry colleague determined to ruin her life. The only catch? That protection looks like Jack posing as her beau. Delphine hesitantly accepts Jack’s offer—and finds her heart being stripped of every predictable and efficient emotion she's ever had.

Jack Worthington believes that his instinct to protect Delphine was the right one, even if it means posing as her boyfriend. But he's determined to stay focused on his research for Lethersby—and to keep his emotional distance after reeling from a broken heart. Yet as the clues to discovering the Lost Queen's story unravel and the court case determining Delphine's fate looms, both Delphine and Jack must step out in faith, choosing to trust that what God has ahead for them is more valuable than the lives they thought they wanted.