I am a fan of Gyles Brandreth's mystery series starring Oscar Wilde. They are intelligent and really take you into the world of the late Victorians and the more unstaid Paris of the day. These are slower-paced mysteries though, and character driven. If you only read thrillers, you may be disappointed in the pace. Also, given that these are Victorians we're reading about, the language and the murders can be a little gothic, though I've always found them amusing.
The main people are the inimitable Oscar Wilde, Robert Sherard (Wilde's real-life friend and eventual biographer) and Arthur Conan Doyle (also knew Wilde in real life, this is before he was knighted). It's March, 1890, London, where Wilde is living at the time with his lovely wife, Constance. Whom, by now, he is neglecting dreadfully.
Wilde has brought Sherard and Doyle to a soiree given by the Duchess of Albemarle, with uber-guest, the Prince of Wales. Oscar points out the gorgeous Rex LaSalle and Robert asks about him. Oh, Oscar throws out, "By night, he claims to be a vampire." When they get a chance to talk to LaSalle, Oscar asks him whose blood he is drinking tonight. LaSalle points and says, "Our hostess, the Duchess of Albemarle."
When said Duchess turns up dead at the end of the night, with two incisions in her neck "deep enough to reach the jugular vein", our protagonists don't know what to think. The Prince of Wales asks Wilde to look into the Duchess' death. He is not assured that death was natural, even though the Duke's favorite doctor, a doctor of psychiatry, not medicine, signed the death certificate as death by heart attack. Conan Doyle is particularly outraged at this.
As always, Oscar's aphorisms are entertaining, even though they frequently contradict one another, depending on the occasion. I liked this bon mot, where Oscar is determined to talk to the Duke, but Conan Doyle is equally sure they won't be allowed in. "He will," Oscar replies. "A man always makes time for those who know his secrets."
This mystery is told in chapters that alternate between people, such as Sherard's notes, Conan Doyle's diary, letters to and from personages, and newspaper articles. One of the reasons it got five stars from me is that very early on, the reader is given a very subtle clue to the murderer. The clue is easy to miss or dismiss, but at the end of the book, when all is revealed, I had an "AHA!" moment where I thought, "I should have noticed that!" The motive is kind of thrown at you at the very end, and the WHO clue is so subtle that I almost took a star off the rating - as I prefer mysteries that give the reader a chance to figure out the murderer (or to THINK he/she has figured out the murderer). But on reflection, I decided my enjoyment of the mystery was high, and so I give it a 4.6, rounded up to 5 stars.