Lord Matthew Devenport has a goal: to erase the large debt he inherited by finding the money his father buried on the estate. His father's dying words only hint at the money's location, thus Matthew spends his nights digging in the gardens. He has less than a month to keep his pledge and has one other recourse: a marriage to save the family estate.

When Matthew invites a few eligible females, their chaperones and several male guests to his estate, Sarah Moorehouse and her older widowed sister, Carolyn, accept. Carolyn has no plans to remarry and Sarah feels she never will. Too tall and without a dowry, Sarah devotes herself to drawing and gardening.

The first evening, Sarah and the females of the Ladies Literary Society of London discuss Frankenstein and decide to create the perfect male, which requires they “borrow” a piece of clothing from the men staying at Devenport's estate. Sarah's duty is to gain one of Matthew's shirts for their project.

After the ladies depart, Sarah spies Matthew returning from the garden, carrying a shovel. Her curiosity about her host grows, and Matthew's explanation of night time gardening clearly reveals he knows little about flowers. When Matthew later finds Sarah in his room, he suspects she might be after the hidden money.

Despite their mutual suspicions, Matthew learns that Sarah's thoughts and desires echo his own, and Sarah comes to believe that Matthew is indeed the perfect man – though unattainable for her. Even so, when she agrees to help him search the gardens, the two lovers are slowly drawn together. Yet time is running out for Matthew and they soon discover they are not alone in seeking the hidden treasure – a hunt fraught with danger and death.

Jacquie D'Alessandro's Sleepless at Midnight is a captivating story, filled with humor, sensuality and heart-felt emotion. The story centers on two lonely people who find trust and love, and I found the mystery suspenseful and the characters delightful, making it a definite keeper. This first installment in D'Alessandro's Mayhem in Mayfair series kept me turning the pages, and I eagerly await her next installment.