Almost certain that is a tobacco plant, Nicotiana - and looks like the crop plant too rather than an ornamental variety. Have you been to the Dordogne recently?!
I think you might be right! No I haven't been to the Dordogne. I can't imagine how it got there, have just found another one growing down the side of the raised bed in my front garden. As long as its not poisonous or too invasive, I guess we can see how it progresses. It does fill a hole in the planter
Wow its pretty lush whatever is! but it does look a bit like a tobacco plant, they make yellow white flowers, we grew them last year.
I suppose we can look forward to hand rubbed Warham loose shag being offered exclusively to HoL pipe smokers. Another first for our community web-site.
Was also pleased to find out while chatting with the gardening gang on the Sustainable Haringey table at the Hidden River Festival that the tobacco plant is a "magnet for moths" - here's some more info on a night scented garden