The Forever Flame: Mercury Raine, Book 4 by Sarah M. Eden

Mercury Raine left London years ago, intending to never go back. Needing to never go back. His carefully guarded past is far too easy to piece together in that city. But the lady who has claimed his heart is being held hostage there, bait intended to draw him out.Determined to find her, Mercury takes the risk of returning to Town. Navigating the dangers that await him there will require all the stealthy survival skills he learned living on the streets of London and more than a little luck. But the peril that awaits him there is far greater than anything even he could imagine.