How on earth did Peter Guillam/Michael Jayston know the combination of the safe in episode 3? And for that matter how did he know the duty officer's room would be empty so he could just walk in and burgle it? And how come the British Airways bag with the Testify file in it wasn't searched and discovered by the guy he gave it to while he went to have the meeting with Alleline?
Surely it can't be that easy to burgle MI5?
Please explain! (Though I must admit I'm loving every minute of it!
One certainly does get the impression that security at the Circus isn’t what it ought to be.
How Guillam broke into the duty officer’s room is one of those details that the book handles very well, but which just wouldn’t have worked if it had been turned into exposition. Here’s the scene described in the book:
He had brought the camera but the light was awful. The net-curtained window looked on to a courtyard full of blackened pipes. He couldn’t have risked a brighter bulb even if he’d had one with him, so he used his memory. Nothing much seemed to have changed since the take-over. In the daytime the place was used as a rest-room for girls with the vapours and to judge by the smell of cheap scent it still was. Along one wall lay the Rexine divan which at night made into a rotten bed; beside it the first-aid chest with the red cross peeling off the front, and a clapped-out television. The steel cupboard stood in its same place between the switchboard and the locked telephones and he made a beeline for it. It was an old cupboard and he could have opened it with a tin opener. He had brought his picks and a couple of light alloy tools. Then he remembered that the combination used to be 31-22-11 and he tried it, four and, three clock, two anti, clockwise till she springs. The dial was so jaded it knew the way.
As far as the bag goes, Guillam was counting on Alwyn not to open the bag since it just a personal bag sent as a favor, and not an official parcel containing files, correspondence, etc. reply share
Also, throughout the series Smiley refers (sometimes jokingly) to the "new" Circus being handled rather imcompetently. He's surprised that Guillam is still in the Circus, and says "He (Guillam) had all the qualities necessary for being expelled: loyal and competent." Even in the final scene, he mentions that the guards protecting Heydon should have checked the clothes that had come from the cleaners, but they didn't. And they even left him alone at night, because "a horror film had just started on tv and they didn't want to miss it." Such lax security measures could be because of a) Alleline's incompetency and preoccupation with his own position, or, b) an ongoing, deliberate act of weakening the Circus by Heydon
I assume that most of the competent personnel were washed-out or relocated when Alleline came to the top position, and the new look, the new name didn't always mean first class work. Hence the combination of the safe not being changed.
If Haydon encouraged that state of affairs, it contributed to his own downfall and death. Guillam manages to take advantage of the lax security as a step in uncovering the mole Haydon, and the poor security at the Sarratt detention centre allows Prideaux to meet with Haydon and then kill him. It is possible that the security would be enough to keep out outsiders, but both Guillam and Prideaux are insiders and know how it works. Then again, "intelligence" services do not necessarily contain intelligent people, "security" services may actually have poor security and so forth.
Probable enough to believe Haydon would have believed he could out-think the other Circus insiders (and I'd wager that would have been true enough, especially Alleline), so he would have been confident that he could still remain several steps ahead of the game while promoting lax security measures that would significantly undermine the organization. After all, he's on the point of formalizing his defection when he's captured, so he figures he isn't going to be around much longer anyway, and is in little enough danger from their fallout; he won't have figured on Sarratt and Prideaux at that point.
I'm the sort to go for the simple answer...I just assumed he'd somehow been got both pieces of information by Smiley. But the answers here do make for a more detailed, and probably more plausible explanation.