the gag that stops even the last expression — "what a truly dumb and silly…"
what a truly dumb and silly way this was, after all this time, to die, a thought which the towel and tape denied expression via the rueful grin with which the best men meet the dumbest ends
Context
The murder weapon is an instrument of silence, the "best call-for-help-stifling gag in the world," and its work is total: it stops not just DuPlessis's pleas but his final human gesture. The one thought he has as he suffocates, the rueful recognition of how dumb a death this is, cannot even reach his own face, the grin denied by the towel and tape. Communication is sealed off all the way down to the smile a dying man would make, so that the interior goes fully dark with no way out.