It's a landmark title in the adventure game genre (at least that's what I think the genre it belongs to). Basically, you go back in time, look at "freeze frames" of past events; freely travel in them in first-person view; look for clues, which are hidden in plain sight or deductible. You solve 50+ murders, making this possibly a whodunit that ends all whodunits. You have to find out the manner in which they died, and who (or what) caused their deaths. At the beginning you only have a group photo of the people with no names. You have to find tons of info: their names, occupations, nationalities, etc. You are given audio clues via dialog, in which different languages are spoken (all subtitled in English). The plot gets silly near the end, involving some hocus-pocus mumbo jumbo that I don't much care for. But it's an unforgettable experience if you like the game and stick with it to the end. Clue-hunting and deduction are domains of adventure game fans, so I think they are the ones most likely to enjoy this.
A YouTuber made a series of videos chronicling the entire gameplay process, dissecting every clue and explaining every deduction, which is thrilling to watch.