Constantine: City of Demons, on CW Seed
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This started as a webseries, with five episodes on CW Seed in March 2018. In October of that year, a movie version of the series, with additional material, was released on DVD and Blu-ray. In January 2019, the first five episodes were compiled into "part one" and re-released on CW Seed, together with the rest of the movie as "part two". (Which is similar to how the web series Vixen was re-released as a movie that combined the two seasons of that series with some additional material.) I always intended to watch the Constantine webseries online, but didn't get around to it before the CW Seed ceased to exist. So I eventually bought the movie on Blu-ray. Although the title character is voiced by Matt Ryan, who also played John Constantine in the live-action TV series Constantine, and there was some speculation that this webseries would be a continuation of that series, it's not actually related. However, the movie version of the webseries is the twelfth film in the DC Animated Movie Universe. (Though Wikipedia doesn't include it in the list of movies because it was originally a webseries.)

Review coming sometime.