Robert Ellsworth, mainly known as Bobby "Blitz" Ellsworth, is the lead vocalist of New Jersey thrash metal band Overkill. He has worked with Overkill since 1980 and has been the lead vocalist of this band since then. Although a bassist, he focuses on vocals in the band.He also did the vocals for the band The Cursed featuring Dan Lorenzo (Hades and Non Fiction) in 2007.