When a Fire-Demon from his parents past kidnaps his fianc?, a timid hydrologist must locate a mythical artefact and uncover its power before the Devil kills his lover and unborn child.

Hi Alice
My original logline had the protagonist as a janitor who had a fear of water, his fear in turns to be his greatest weapon at the end of his story. But being a Janitor and phobia of water didn't work out great as Janitor's use water in every day use.

I like the idea of "building the device" But I'm not sure that's the path I want this story to take.
Long story short, there is a hidden power inside the artifact, a power that his mother once possessed.

I think I'll work with the logline a bit more and go along with the phobia of water, his occupation will obviously change.

Thanks for the feedback.

Structurally, you've got a lot of interesting pieces here with high stakes and irony. I'd lead with the main character and his flaw, then his problem, then what he's going to do about it.

In terms of story, I feel like the world's chock full of mythical artefacts to save the day. Can I make the suggestion that instead of finding some ancient being's Sceptre of Highly Specific Use, he has to instead find the plans, then build the device? That could also be a complication in a story of finding the device but discovering it no longer functions. Also, making your antagonist's weakness (water) your protagonist's strength (hydrology) tips the scales a little too far in his favour and makes it an obvious win. If anything it should be the other way round, with the antagonist's strength being your protagonist's weakness, which he must then overcome to succeed.