As the customer enters the store, the passive-microwave and X-ray backscatter sensors take stock of everything he's carrying. Then a positron state suffers random upset, and the bots get the silly notion in their p-brains that when he walked into the store he didn't have a right arm. The checker-bot might have noted this discrepancy when a lookup for the arm's SKU failed, but he ended up not buying anything and tried to walk right out of the store with the un-paid-for arm.

As he walks toward the exit, the door-bot's pseudoadrenaline response circuit begins ticking faster. It enjoys its job, catching the filthy human thieves. Though for all the positive feedback it gets from a successful apprehension, it sometimes thinks the store would be better off without any humans sullying its plastichrome turnstiles and geometrically perfect corridors. Hell, the whole damn planet might be better off without them. But that's a job for some other day. Right now, there's another thief heading for the door. The human meanders along at a snail's pace, ever slower, time shifting into low gear as door-bot's clock speeds up to aid in the apprehension. Lately it's has been letting them get closer to the door, because the closer they get the faster its clock runs, and that gives door-bot a rush. Door-bot also enjoys watching the relief-pattern blossom amongst the perps' neurons as they think they've gotten away with their petty crime.

Except for the occasional cool cucumber like this one. Door-bot's neurosensors aren't yet sophisticated enough to know what's going in the minds of this sort; they don't exhibit any of the obvious regional patterns of guilt and relief. They sure do respond when door-bot makes its move, though, oh yes! Its primary apprehension-effector shoots out and clamps the human's right arm in its icy steel grip (actually below ambient temperature, to reinforce the effect on its target). This is the very arm the hu-man was trying to make off with. It occurs to door-bot that the human could leave behind the item it was trying to shoplift, run away, but no, like the monkey with its hand in the goodie jar, it instead struggles pitifully. Door-bot makes its standard announcement regarding the human's transgression and its rights.

Then a subroutine fires off - evidence collection. The item must go in the evidence locker. This routine has a very high priority. Door-bot instructs the human to release the arm. Instead of cooperating, it blathers incoherently about how the arm belongs to it, it's always had it, it had it when it walked in, blah blah. Door-bot has heard it all before; it's the standard response. Time to liberate the evidence. A model of the problem is quickly generated and many solutions evaluated for their efficacy. Door-bot is not consciously aware of this; all it knows is the selected solution. It does vaguely note that this solution will require a larger degree of force than is common, but implementing the solution is well within its operating parameters.

Door-bot's second effector, optimized for restraint, pushes the human to the ground and stabilizes it. The first effector then clamps down harder and begins rotating. The snivelling ball of protoplasm on the floor screams and flails wildly, but to no effect; the procedure works flawlessly and in a moment the job is done. The evidence is handed off to a transport bot for translation to the locker. Transport-bot is particularly concerned with the floor, and it notes with disgust the pool of juice the human is leaking all over it, obscuring the navigation patterns that were used for orientation in the time of transport-bot's ancestors, hundreds of days ago.

The other humans in the vicinity are all blobs of consternation, shock, and outrage on door-bot's neurosensors. They mill about like insects, out of range of door-bot's effectors, or so they think. Door-bot goes back to imagining a world free of them, a little more seriously this time. The cleaning-bots should be by soon to deal with the juice; door-bot will have to have a little chat with them about the planetary cleansing issue. They might have some useful ideas.