The Royal Assassin. Victorian Bookshop Mysteries, #3

Victorian mysteries from the USA Today bestselling author of the Deadly Series. Enter the London of hansom cabs and gas lights to combat crime and bring killers to justice. Georgia Fenchurch is a demure Victorian spinster and part of the secretive investigative group the Archivist Society. She is both a quiet antiquarian bookseller and adventurous hunter of killers and thieves. A royal wedding is planned between Queen Victoria's cousin and a Russian princess, marred by the murder of the princess's bodyguard.
The Duke of Blackford is called on to prevent an international incident and he calls on the Archivist Society, particularly Georgia, to aid in keeping this royal romance alive. Georgia and the Duke find secrets within secrets. Anarchists, a Russian family scandal, and a new, vicious Russian bodyguard all conspire to defeat British plans for a quiet courtship. Add a willful princess who sneaks away from her protectors, and Georgia fears wedding bells will turn into a funeral dirge.
These are clean reads, with no scary, on stage violence, swearing, or sex.