I know this one is technically already out but only in America. I can't wait to see if someone picks it up in the UK
Darker Still by Leanna Renee Hieber
Published by Source Books
The Picture of Dorian Gray meets Pride and Prejudice, with a dash of Dr. Jekyll and Mr. Hyde.
New York City, 1882. Seventeen-year-old Natalie Stewart's latest obsession is a painting of the handsome British Lord Denbury. Something in his striking blue eyes calls to her. As his incredibly life-like gaze seems to follow her, Natalie gets the uneasy feeling that details of the painting keep changing...
Jonathan Denbury's soul is trapped in the gilded painting by dark magic while his possessed body commits unspeakable crimes in the city slums. He must lure Natalie into the painting, for only together can they reverse the curse and free his damaged soul.