Secrets in the Dark is an adventure written by Dan Hass and available on DriveThruRPG both separately and as part of a low-level adventure package. The adventure is designed for 1-6 first level characters, although I’d be quite wary of running it with a single PC without modification. A party of characters is generally better at recovering from bad luck; running single character adventures has never been something that D&D has done well.
The adventure is short and simple, but not without merit. It consists of six encounters, most of which are in a small cave complex.
These caves are the lair of two ne’er-do-wells, a dragonborn of the Red Dragon Cult and an awakened giant wolf spider. The two tolerate each other’s presence and have both caused trouble for the locals in their different ways, allowing the DM to use the capture or killing of either of them to be a hook for the players; this may also lead to the second villain appearing when the players least expect it.
Apart from the two villains, there are a couple of traps and tricks and a couple of easier combat encounters to round out the adventure. I’m a little wary of the lethality of some of the encounters. A trap that deals 2d10 damage to everyone within range? That’s a potential TPK right there!
The adventure is playable with just the Basic D&D 5E rules. It includes only the statistics of the unique monsters and traps, with page references to the main books (or Basic rules) for the other statistics. Scaling notes are given for each encounter; I’m very happy to see this for the solo monsters.
Although there’s nothing ground-breaking about the adventure, it looks enjoyable to run and play. It might be better suited to second-level characters, but it should prove to be an entertaining night’s game, especially if you take the opportunity to role-play the villains appropriately.