The recent poisoning on British soil of Sergei Skripal, a former Russian military intelligence officer who acted as a double agent for the UK's intelligence services, and his daughter Yulia with a very rare nerve agent of the Novichok type appears almost certainly to have been conducted by the Russians. While the attack is part of a long chain of similar incidents, it was an overwhelming event diplomatically, politically, practically, and in terms of intelligence. Two similar incidents in London exhibited common elements linking them to the Skripal attack. Together, they shed light on the apparatus that might be responsible.