But something in her voice - harsh and shrill and weighed down with frenzied alarm — sent a chill…
Mismatched dashes.
2.
Both of whom set about assisting another man—injured and moving slowly—who was placed…
Your dashes here have no spaces before and after as they do in other sentences.
3.
Tabitha and the others started to descend the steps, save for three members of this new contingent — a skinny, older man and a younger man with dark brown hair who looked no older than twenty. Both of whom set about assisting another man—injured and moving slowly—who was placed upon a utility cart and was attempting to sit up.
I believe this should be one sentence. “Both of whom” refers to the previous sentence so I would suggest:
…no older than twenty, both of whom set about assisting…
4.
It crumbled up like no more than a bundle of straw and then disappeared into the black hole.
Did you mean “crumpled” or “crumbled?” I picture it crumpling but maybe you meant it broke into pieces and crumbled.
1.
But something in her voice - harsh and shrill and weighed down with frenzied alarm — sent a chill…
Mismatched dashes.
2.
Both of whom set about assisting another man—injured and moving slowly—who was placed…
Your dashes here have no spaces before and after as they do in other sentences.
3.
Tabitha and the others started to descend the steps, save for three members of this new contingent — a skinny, older man and a younger man with dark brown hair who looked no older than twenty. Both of whom set about assisting another man—injured and moving slowly—who was placed upon a utility cart and was attempting to sit up.
I believe this should be one sentence. “Both of whom” refers to the previous sentence so I would suggest:
…no older than twenty, both of whom set about assisting…
4.
It crumbled up like no more than a bundle of straw and then disappeared into the black hole.
Did you mean “crumpled” or “crumbled?” I picture it crumpling but maybe you meant it broke into pieces and crumbled.
5.
…who was equally confused as David.
Should this be:
…who was equally as confused as David.