What's this?

I give in-give us a clue?

Does anyone have any idea what this plant is please?  It gets to about 5 feet tall, it doesn't flower (although it looks like it wants to!) and seeds quite freely.  I inherited them with the garden when I moved in about 5 years ago and it's one of the only plants I have still to identify.  All help is much appreciated!  Emma

That's so helpful - and so quick!   Thanks so much

If it doesn't flower, where do the seeds come from?

The flowers are tiny things nestled right down in the green bracts at the top of the stems.

Yes it's one of the euphorbias - be careful not to get the white latex-like sap on your skin as it can cause a painful rash, particularly in sunlight (no danger at the moment then ).  It's also meant to deter moles. 

I've done a bit more research - it does flower but they don't have petals.  Later on, bulb-type lumps (sorry, not very good at this!) appear and the seeds are in there,  As with all euphorbia, it's poisonous and has latex in the skin so can be an irritant.  It's considered a weed, but so is buddleia according  to Network Rail, so it's staying in the garden for now.