Ms Brooks was lifted by detectives from Operation Weeting - Scotland Yard's investigation into mobile interceptions by News International - accompanied by officers from Operation Elveden, the enquiry into allegations of naughty payments to police. Hers is the tenth collar the Yard has felt since the fresh investigation into phone hacking was launched in January.
But sadly, today's arrest has quickly cast serious doubts over whether Brooks will be able to appear before the Culture, Media and Sport Committee on Tuesday along with former boss Rupert Murdoch and son James . It's unclear to what extent she'd be able to answer questions if she did appear, without compromising the police investigation into her vile past - which of course may come to nothing.
So the timing of Brook's arrest seems deeply unfortunate, to be sure. Perhaps she still has influential friends in high places. Or, she's torn the hard drives with details of others' wrong-doings from ex-NOTW machines, and put them in a nice safe place. Either way today's events smack of the establishment closing ranks. Mere conspiracy theory? You decide.