I don't think there's anything subtle about jimson weed and its ilk. This site seems to have a good writeup:

The plant is a member of the nightshade family, which also includes tomatoes, potatoes, petunias and tobacco. Members of this family typically contain organic compounds that range from beneficial to toxic. Compounds in sacred datura are psychedelic, and the plant was important to native Americans in their sacred ceremonies. However, if misused, these same compounds are fatal.

Another site doesn't hesitate to spell out the dangers:

Then there are the folks who have misused Sacred Datura because compounds in the plant are psychedelic and with misuse death is inevitable. The effects of ingesting Sacred Datura can happen within minutes to hours. Symptoms include; delirium, thirst, distorted vision, uncoordinated movement, high temperature, a rapid and weakened heart beat, convulsions, coma, and death.

Someone dosed with it is more likely to go into convulsions than go into their bank account and empty it for you.