^ Quite a scary way to go, with all the realistic hallucinations too. But like an opiate overdose, an anticholinergic overdose produces a set of rather striking effects that are highly specific to this toxidrome, and are readily recognized by any seasoned emergency response team. Moreover, there's a well-established protocol for treating anticholinergic toxicity, including an antidote (rivastigmine or neostigmine). In other words, if someone sees you in this overdosed state and gets you immediate medical attention in a not too remote place, your prognosis isn't all that bad, although the experience will be subjectively hellish.
Someone by now must have written a story about a sadist who overdoses his victims with a paralytic neuromuscular junction blocker like cisatracurium (Nimbex) and then rapes or tortures them. These drugs have only one effect, and that is to make all the skeletal muscles in your body go entirely flaccid and unresponsive to your volition. Your sensorium (including pain) and memory remain entirely intact, and there is absolutely nothing you can do.
You know, I really should stop now with this. This is merely the darkest reaches of my imagination, but all sorts of people read these boards and get ideas from them, and therefore me writing things like this here could be seen as skirting the edges of my Hippocratic Oath.