A mortal likeness: a Victorian mystery / Laura Joh Rowland.

Enhanced descriptions from Syndetics:

Fresh off the Jack the Ripper case, Sarah Bain and her ragtag team of investigators search for the missing child of a wealthy banker-who may be more perpetrator than victim

A photographer in 1889 London, Miss Sarah Bain runs a private detective agency with her friends, Lord Hugh Staunton and former street urchin Mick O'Reilly. Their sole credential is that they solved the Jack the Ripper case, a secret they can never tell because they did it outside the boundaries of the law. Their new big case arises when a wealthy banker, Sir Gerald Mariner, posts a handsome reward for finding his missing infant. All of London joins in the search. But Sarah has an advantage-a photograph she took during a routine surveillance job, which unexpectedly reveals a clue about the kidnapping.

After Sir Gerald hires Sarah, Hugh, and Mick to find his son, they move into his opulent mansion and discover a photograph of baby Robin. It eerily resembles postmortem photographs taken of deceased children posed to look as if they're alive. Was the kidnapping real, or a cover-up for a murder? Is the perpetrator a stranger, or someone inside the troubled Mariner family?

The case hits close to home for Sarah as it intertwines with her search for her father, who disappeared after he became the prime suspect in a murder twenty-three years ago. She finds herself on the wrong side of the law, which threatens her budding romance with Police Constable Barrett. But Sarah must uncover the truth about Robin's kidnapping, and her own family, before her past catches up to her in A Mortal Likeness , the gripping follow-up to award-winning author Laura Joh Rowland's The Ripper's Shadow .