I suspect that I'm just a few keywords away from figuring this one out, but I either listened to an audiobook of this, or read an ebook, in August of 2022 or 2023 because I remember partaking of it during nighttime walks during a family trip to Ocean City. The male lead is a mythology professor at a university in New York City. At the beginning of the book, he's lost his girlfriend (or maybe a close ex?). I don't remember if she broke up with him, disappeared, or was found dead. Shortly thereafter, I think he learns that his position was about to be terminated, which becomes plot relevant later. The female lead is Artemis, a Greek Goddess who has survived until the present day in part because there's always a need to for someone to protect women who are being targeted by violence. There are a series of ritual murders happening in the books, with Artemis contacting the professor to try to get help with puzzling out who's doing them.
I remember that the murders are tied to some sort of "mystery cult" tradition that the male lead was the leading expert on, and which he basically portrayed as something closer to the more esoteric features of a fraternity, as an excuse for getting together and partying rather than the stated purpose of ensuring a fertile harvest for the city. Artemis, on the other hand, is convinced that whoever is performing the rituals is trying to draw power for their godhood (one of the themes being that some of the Greek gods like Zeus and Hera are dying out due to lack of worship while others are either becoming more mortal, or thriving on pop culture worship, like Hermes continuing to get a boost from his portrayal in flower delivery and mail), and a later plot point is Artemis considering letting the ritual go through so that she can save her mother, Hera. I do remember it as that the professor is heavily invested in the idea that Greek mythology/magic is all symbolism and superstition, which is a source of conflict between the two of them. I remember most of the rituals involving someone being killed, with ones that pop into my head involving someone being killed in Central Park and found the next day by the police, someone who is bludgeoned to death by a giant tusk (of an extinct boar?), someone who is placed in a room with live venomous snakes suspended from the ceiling (there also being a bit where it's pointed out that whoever did this had to steal a ton of snakes from zoos and private collectors, and may have had a significant impact on the various species involved since so many rare breeds had to be euthanized), and a killing on live TV (I want to say during a filming of Saturday Night Live). I'm also remembering one of the rituals involving a young girl with cancer being kidnapped from her hospital ward, but I want to say that she was found not only unharmed, but cured of her cancer by the magic of the ritual (that might have been the one with the snake, with it being associated with Asclepios and his staff).
Due to him constantly showing up around murder scenes, the professor becomes a person of interest by the police, and has to dodge them while trying to solve the murders (I also remember him having to break into his own office at the university to get his notes, although I don't remember if that was a police thing or them having fired him suddenly) with him getting in via the drop ceiling, and I think escaping by Artemis using her bow to set up an impromptu zipline. I remember a scene where they go out to see a movie (I think largely to get them off of the streets due to the police looking for them), they wind up watching an action movie with a female lead, and afterwards, Artemis encounters a young girl who recognizes her as a goddess (apparently a common trait in the young), but mistakes her for the lead of the film (who is not a Greek goddess, but merely a human doing improbably heroic things), which oddly provides a worship boost. I think that, early on, the police were interested in his input as an expert on the mystery cults, and it's only further on that they're convinced he's actually the killer (or knows who is). Oh, and one of the female police officers recognizes Artemis from when she had a persona who was a police officer several decades ago. I think that gives them a little bit of leeway with the police as Artemis presents herself as her prior self's niece or granddaughter, and the person who recognized her is fairly high up in the hierarchy.
It later turns out that the professor is something special, a type of mortal who draws the gods to him and can be a source of power to them if he evangelizes them. I also recall it being established that an old college roommate is actually Dionysus, with the protagonist having just assumed that the constant drugs and sex were just college benders. I remember a scene where the two leads visit him, I think because they were trying to track down a drug used in one of the murders, and Artemis recognizes him as a god on sight. I think, during that scene, he successfully drugs them with one of his concoctions in their drinks, but I don't recall if his intent was malicious (because he's part of the mystery cult), self-serving (he's hoping that the rituals will bring him power and he doesn't want them interfering), or simply part of his nature (it's made a point that one of the reasons the protagonist broke off ties with him was that his mix of drugs and sex was basically date rape a good bit of the time).
I remember that the book ended with them managing to foil the villain's plan (I remember the climax involved a grotto/spring in Central Park that has some sort of Native American holy site baggage, alongside the more Greek architecture that had been plastered on it). Some of the Greek gods have died in the process of the narrative (killed by Artemis in at least one case, which was anathema, but also at least one, Hera maybe, who dies from lack of worship), but Artemis has found her path forward, with I think some degree of reflecting that this professor is making her reconsider the "virgin goddess" aspect. It felt like the first book in a series, but I don't think I read it past the first one.
The book was in English, and I think was a fairly standard novel length, 200-300 pages, although I did consume it in a digital format, which generally leaves the actual number of pages fairly hazy. Other bits and pieces I recall:
- Apollo was also active, and I think he was considered the likely villain throughout much of the book due to him having retained his power. I think he's either an actor, or works with actors as an agent.
- I think Zeus had already died off at the start of the book
- Hades has a lair somewhere in the New York subway system, which they visit
- Artemis has a bronze bow that she carries as her primary weapon
- Artemis also has a dog, who is of high, but animal, intelligence. They don't talk to people, but I think they're able to follow fairly complex commands. I have a vague memory that her animal companions are unusually long-lived (decades old and still highly active), but not immortal
