You're hitting on one of my favorite dynamics, the whole twins-in-peril thing. It's fascinating because it plays with two extremes—the inherent, almost saccharine 'cuteness' of the twin bond, and the raw, high-stakes desperation of a crisis.
When it's done well, the cuteness isn't just for decoration. It becomes a shorthand for their deep, intuitive understanding. They don't need full sentences; a glance, a shared childhood memory invoked by a phrase, that's their secret weapon. The desperation then heightens that bond to a breaking point. I've seen it where one twin, usually the more outwardly vulnerable 'cute' one, will do something recklessly brave to protect the other, flipping the expected roles. Their synchronization in a fight scene can be terrifyingly efficient, like a single mind operating two bodies.
But the real tension often comes from the fear of that bond being severed. The crisis forces them to confront life without the other. That's where the emotional weight lands—not just in surviving the external threat, but in realizing the co-dependency might be a vulnerability itself. It's a messier, more interesting exploration than just 'twins help each other win.'