Agents Of The Odd is a modern conspiracy-supernatural osr adventure game.
It's 46 pages, with an easily readable but very text-heavy layout, and it runs off of the excellent OSR-pared-down-to-its-bones engine of Into The Odd.
It's written in-character, as a training manual from a dystopian government, so it takes a little more work to decipher than Into The Odd's rules, but it's still pretty clear and well-explained.
The mechanics are pretty straight up Into The Odd, with a few small tweaks to better contour the game to a more mission-based format. If you haven't played ITO, think original D&D---but you can have a new player up to speed and playing in five minutes without losing any of what makes the game mechanically fun.
From a GMing perspective, Agents is solid, and gives good advice in general for running games in its supernatural investigation genre. It also comes with an (admittedly extremely straightforward) sample adventure, which digs into a cool bit of folklore.
Overall, if you like Delta Green, Trail Of Cthulhu, F.I.S.T., or other games of modern conspiracy-horror---and if you'd like to try an extremely-quick-to-pick-up version of the above---grab Agents Of The Odd. It's well-made, fun, and has quite a bit of its own flavor to set itself apart from other games in the genre.