Call me Rosa Klebb, but surely there has not been a spy drama like it since James Bond’s Goldfinger as we all learn more daily about the murky goings on at Credit Suisse.

Chief executive Tidjane Thiam is fire-fighting a scandal after revelations that private detectives were hired to follow former wealth management chief Iqbal Khan, a man now in the top echelons of rival UBS as co-head, wealth management.

And we all thought that Swiss private banking secrecy was dead.

The drama has everything, including devices that even “Q” couldn’t dream up, such as Threema, the super secretive Swiss messaging app use...