Christmastide means dancing, kisses in the snow... and murder most foul.

Ever since May Day, the Honorable Caroline Ives has felt at sixes and sevens, partially due to the mercurial courtship from a certain handsome, if grouchy major, and partially because she's been anxious to discover where she fits in the beau monde. What society deems proper isn't what sets her soul on fire, but lending a hand to the major to solve mysteries?and enjoying his kisses?is. She wants him to secure her future, but he's dragging his feet regarding the romance.

Life has changed for Major Felix Kourier. After partnering with the delectable and intelligent Caroline to solve a mystery, he suddenly has a new purpose for his existence. As he's tried?and failed often?at courting the viscount's daughter, he wonders if he should ask for her hand, for she is much like enjoying a rare sunny day. Perhaps doing so at a Christmastide ball would prove just the thing to secure the delightful lady who has turned his life upside down.

While the Christmastide season envelops London, fate interrupts the heady romance when the body of a prominent peer is found on the steps of St. Paul one rainy afternoon. What's more, he was one of Felix's friends. As a case unfurls, the unlikely pair is once more in their element. Investigating during the holidays is difficult, especially when a killer is adamant secrets remain unspoken. Staying a step ahead is key, and if the deductive couple wants their passionate courtship to proceed, they'll need to prove more brilliant than a murderer's mayhem beneath the mistletoe.