Candela Obscura is a spinoff podcast from Critical Role. The show itself is not set in the same world or even using the same game system, but it features many of the same cast members and masterminds behind Critical Role. Candela Obscura is an actual play for a game of the same name, which was published by Darrington Press, Critical Roles gamng company.
The show runs in smaller, self contained series, that are all loosely tied together within the game's setting. Each arc has run for 3 episodes and features a new "circle" doing an investigation for the organization of Candela. While some circles have recurring cast members, each one features its own characters and they are mostly self contained from the previous story arcs. The game itself is an investigative mystery game that has some very eldritch undertones to it.