Setting aside the specifics of my particular plot for a moment, I have need of plot inspiration: how do I set up an escape from a death trap that seems plausible after the fact, and not too contrived?
I'm stuck figuring out the details of such a scene in my story. It's an adventure story, similar in theme to indiana jones or the lara croft series: adventurers exploring a temple, baddies, spells and actual magic, a treasure to be reclaimed, etc. I'm dealing with death traps: the characters are to be sacrificed at dawn in a blood ritual, and they need to discover a way to escape right before the spell is cast. How do I have protagonists escape a death trap? What tropes or mechanics are used to get the heroes out of immediate danger in a way that forces the big baddie to confront them directly?
I considered having them break out of their shackles, but then the villain was inept and this is no good; also, way wait until the ritual to escape? I considered having one of the minions screw up and give the heroes a lucky break, but that's too ... easy. I figured maybe they look around the chamber and see a switch or a trap or something they can interact with, but how could they do so if the villain has them bound? I don't want them to be simply lucky -- it should take both cunning, perception, and luck -- and I want them to have only a brief moment of escape before being forced to face the main antagonist.
And I certainly want the villain to seem competent, not inept and arrogant.
If this question is too specific or not on-topic for this QA site, I apologize; I'm going off this post for justification: Is a "Help me generate plot ideas?" or similar question on topic?