If you loved Justice League Dark, try DC Showcase - Constantine: The House of Mystery
A bridge between a film you've already seen and one most people haven't. DC Showcase - Constantine: The House of Mystery has roughly 6.2× fewer votes than Justice League Dark — it's a deeper cut, not a mainstream recommendation. Here's what they share, and what the second one does that the first one doesn't.
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Justice League Dark
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DC Showcase - Constantine: The House of Mystery
What they share
Theysit in Action / Adventure / Animation / Horror territory. If that's the register that drew you to Justice League Dark, the second film will land in a comparable space — through a different lens.
What DC Showcase - Constantine: The House of Mystery is
Darkness in the House of Mystery on a stormy night a ticking clock. Shredded bodies and friends turned demons. A twisted horror from the DC animated universe.