RPS apparently never met a detective game it didn't like. There are six on our list of the best games of 2022, for example. If the glowing praise of the team here convinced you to try Chinatown Detective Agency or The Case Of The Golden Idol, then you might want to wait a little while longer before buying them. One of next year's genre-specific Steam sales will be the Steam Mystery Fest, running from February 20th-27th.
The event will focus on games about "the spirit of investigation and solving mysteries", and will include not only discounts but new demos on "current and upcoming games". Valve announced the fest earlier this week, inviting game developers to submit their eligible games for inclusion.
Earlier this year, Valve announced some tweaks to how they operated sales, lowering the 'cooling off period' between discounts for developers and introducing several genre-specific sale events. In 2022 those included sales and fests dedicated to sims, JRPGs, racing games, roguelikes, survival games, and more.
Mystery games - particularly those about detectives solving crimes - have traditionally been in short supply. That's unusual given the prevalence of crime shows, movies and novels, although more understandable given the challenges of designing a mystery that players themselves can solve. In recent years, several developers seem to have cracked the genre, with Return Of The Obra Dinn reigning supreme on this year's RPS 100.
Obviously there's no way of knowing what games will be discounted in February, but the timing is good.