Secret City: The Sunken Kingdom

The king of Merfolk was a generous ruler, but his daughter's thirst for power resulted in the devastating war between the four races. Defeated, Princess Tenebris escaped, and got lost along with her realm... until a dwarven explorer stumbled upon an artifact of the legendary kingdom. Now that the curious dwarf was found turned into stone, you, Detective, have to find the murderer and avert a new menace in store for the Secret City. Plunge into the mysteries of the River Thames in this fantasy hidden object adventure game.