They failed to convince us that the still-living Sergei Skripal, the alive and fairly well Yulia Skripal, and DS Nick Bailey who simply got up and went home after a few days in hospital, had been poisoned by one of the deadliest substances known to man.
So last night's Newsnight was instead largely given over to the "heroic" NHS staff involved. There was, however, no mention of the parlous state of the NHS in general.
Newsnight ended with Kirsty Wark's attempt to turn Richard Madeley into a figure of fun for having shut down his interview with Gavin Williamson after Williamson had simply refused to answer the question.
On Newsnight or the Today programme, Williamson would never have been asked anything so impertinent in the first place, he would have been allowed to blather on for 10 minutes without saying anything at all, and he would have been thanked obsequiously for having appeared. But he was not on the BBC this time.