News that Abdelhamid Abaaoud, believed to be the ringleader of the Paris attacks, had died during a French police raid came as a welcome win for investigators.
At the same time though, they realise the Belgian jihadist's whereabouts was just one strand in a complex and evolving investigation being pursued under the enormous pressure created by the knowledge that their enemy may launch murderous follow-on attacks at any moment.
On Wednesday evening, Paris prosecutor Francois Molins caused consternation when he revealed that "a new cell was neutralised" during the bloody raid of a flat in Saint Denis and that "this team would have been able to carry on other attacks".
Suddenly we realised this was not those who'd escaped Friday's atrocities and that even if Abaaoud was proven to have been there, it was a different cell, heavily armed, that according to some official briefings was about to perpetrate a massacre in the financial district of La Defense.
So we have received a salutary reminder that the journalistic narratives of an "eighth man" or an "escaped mastermind" often get in the way of understanding what is happening in a case like this.
It might be done with integrity (based on official sources leaking information for their own reasons) or it might be no more than a social media echo chamber where some speculation soon becomes a "fact" bemused investigators are then quizzed about.
Their inability to answer some of these questions might be seen as suspicious, whereas in fact it is no more than puzzlement.
Hundreds of swoops
The question of how many people the authorities are looking for is in itself a complex one because the number is being added to all the time.
When Mr Molins revealed on Wednesday, for example, that one of Friday's Stade de France attackers and one of the Bataclan theatre killers remained unidentified, it indicated a certainty that once those identities had been established it would generate additional lines of inquiry, raids and quite probably arrests.
There have been so many of these police swoops - several hundred since Friday - that one has to ask whether they are simply taking this opportunity to bring in all sorts of jihadist suspects or whether the list of people they are looking for is much larger than we might suppose.