| 1 | Keir | MacRae | Protagonist. Scottish owner of MacRae Distillery. |
| | Luke | Marsden | 3rd son of an Earl. |
| | Lady Merritt | Sterling | Protagonist. Sister of Luke. Owner of Sterling Enterprises. |
| | Joshua | Sterling | Merritt's husband. Deceased. |
| | Owen | | One of Keir's employees. |
| | Ranald | Slorach | One of Keir's employees. |
| | Marcus | Marsden | Earl. aka Lord Westcliff. Father of Merritt and Luke. |
| | Miss | Ewart | Merritt's secretary. |
| | | Merritt | Veterinarian who assisted in Merritt's birth. |
| 3 | Mr. | Gruinard | The supervising exciseman. |
| 4 | Daisy | Swift | Merrit's Aunt. |
| 5 | Gordan | Catach | Elderly lawyer from Islay. |
| | Sebastian | Challon | The Duke of Kingston. Owner of Jenner's. |
| | Horace | Hoagland | Managing steward of Jenner's. |
| | Lachlan | MacRae | Keir's father. |
| | Ivo | Challon | Youngest son of the Duke of Kingston. |
| 7 | Mrs. | Chalker | Merritt's cook. |
| | Jeffrey | | Merritt's footman. |
| | Garrett | Gibson | Doctor. |
| | Ethan | Ransom | Garrett's husband. Assistant Commissioner of the Metropolitan Police. |
| | Cormac | Ransom | Garrett and Ethan's son. |
| | Jenny | | One of Merritt's housemaids. |
| 9 | Lillian | Bowman | Merritt's mother. Lord Westcliff's wife. American Heiress. |
| | Elspeth | MacRae | Keir's mother. |
| | Neil | | Keir's friend when he was younger. |
| 12 | Lady Phoebe | Ravenel | Merritt's best friend. The Duke of Kingston's daughter. |
| 13 | West | Ravenel | Phoebe's husband. |
| 14 | | Kent | Doctor. |
| 16 | Culpepper | | Duke of Kingston's valet for 25 years. |
| 17 | Evie | | Merritt's mother. The Duchess of Kingston. |
| | Cordelia | | aka Lady Ormonde . |
| | Lord Ormonde | | Cordelia's husband. |
| 18 | Henry | | Phoebe's first husband. Deceased. |
| | Eden | Ravenel | Phoebe and West's daughter. |
| 22 | Lord St. Vincent | | aka Gabriel. The Duke of Kingston's oldest son. |
| | Raphael | Challon | The Duke of Kingston's second son. |
| | Seraphina | Challon | Merritt's younger sister. |
| 23 | Wallace | | Keir's dog. |
| | Ajax | | Family dog of the Challon's. |
| | James | | The Duke of Kingston's footman. |
| 25 | Sir George | Stevenson | Newly appointed British Ambassador. |
| | Lady Sylvia | Stevenson | Sir George's wife. |
| 28 | Annabelle | Hunt | One of Lillian's closest friends. |
| 33 | Sid | Brownlow | Former member of the 1st Dragoons special regiment. |
| 35 | Fia | Slorach | Wife of Ranald. |
| 36 | Errol | MacTaggart | Sheriff of Islay. |
| 37 | Duffy | | One of Ethan's agents. |
| | Wilkinson | | One of Ethan's agents. |
| 38 | John | Peltie | Working for Lord Ormonde. |
