Dinah nods, and turns her back on him, just to jog to the other closing wall, spin and race at him.

As she approaches, she counts her steps:

"Three! Two!" On one she plants the ball of her foot into his stirrup and leaps up.

She easily grabs the uppermost ridge and jams her fingers in, pulling her feet up to the same ridge.

Oh, for a bat-grapple.