Without getting spoilery, I really do NOT like the end of this one. Compare and contrast with the solution chosen by Sapphire and Steel in story 4 of that series - explanation below the cut:
My problem here is that this is a completely unrepentant monster. The Sapphire and Steel story is about an entity that can invade any photograph and use it as a gateway to attack the physical world. Their solution is to keep it trapped in a single photo forever, to stop it hurting anyone else. It works much better for me.
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