Not a "B" I'm afraid

Flower Friday this week has the theme "B" but unfortunately this is a hover fly and my imagination doesn't stretch very far!  More Sweet Williams that seem to be thriving in a quite neglected corner - perhaps that is the reason!

I'm afraid I'm going to use another "extra " in the hope that someone can identify this strange visitor.  The pictures aren't very clear as he darted from one flower to another sucking up the nectar.