The Jasper Claxton Mysteries (Book 2 The Ghost from the Molly-House)

Jasper Claxton was only twenty when he died in the early part of the 18th century in Newgate prison in London, because of gross injustice and cruel, barbaric beliefs, and practices. He's now a super ghost who travels through time, helping others who are either the victims of crime, or troublesome and dangerous spirits. The Jasper Claxton Mysteries is a collection of three ghost stories that mix actual places, and historical events, with fantasy.
The first story is set in Haiti in 1933. While searching for some ancient stones that are said to have mystical powers, Jasper finds himself helping MI6 who are looking for a missing agent while investigating dark voodoo rituals, drug smuggling, and modern-day slavery.
The second story is set in Paris in 1900. Jasper works with a perfumier and spiritual medium, to try and stop a sinister Brotherhood, who are trying to become immortal and want to control the supernatural and the natural order of things.
The third story is set in Venice, Italy in 1934. Jasper finds himself back with MI6 who are investigating a research centre and sinister Artificial Intelligence.