Datura stramonium or Devil's Snare - other common names: augushka, jimson weed, ditch weed, loco weed, angel's trumpet, and devil's trumpet - has been found in Phyllis Abbott's garden in Suffolk.
A member of the nightshade family and can cause hallucinations if consumed, as recreational drug, in small doses but death if overdosed.
I have followed the story for the last couple of days and realised that this plant grows in abundance around us here in France and I have often wondered what it was.
Even my neighbour M. Bertrand shrugged his shoulders when I have asked him in the past (that's not uncommon though) - I have always been of the thought that it was a cultivated plant that has self seeded because it doesn't look like a typical weed.
The bugle like cream flowers very rarely open and the prickly fruit is very attractive - turning a deep red as it ripens.
I took these photos this morning about half a mile from my house - click to enlarge.