"Beats me," I said. "Maybe they're building practical-joke circuits into robots these days. Let's give 22A a good going-over, Min. If those robes are up to something I want to know about it." We did--and found the rest of the girl mech. All of her, that is, except the head. The working parts were lightly oiled and wrapped in cotton waste while the other members and sections of the trunk were neatly packed in cardboard boxes with labels like Solenoids FB978 or Transistors Lot X45--the kind of boxes robots bought their parts in. We even found a blue dress in one of them. "Check her class and series numbers," Min suggested. I could have saved myself the trouble. They'd been filed off. "Something's funny here," I said. "We'd better keep an eye on every servo guest until we find out what's going on. If one of them is bringing this stuff out here he's sure to show up with the head next." "You know how strict Minor Planets is with its robot personnel," Min reminded me. "We can't risk losing that stopover contract on account of some mech joke." Minor Planets was the one solid account we had and naturally we wanted to hold on to it. The company was a blue-chip mining operation working the beryllium-rich asteroid belt out of San Francisco. It was one of the first outfits to use servo-pilots on its freight runs and we'd been awarded the refuel rights for two years because of our orbital position. The servos themselves were beautiful pieces of machinery and just about as close as science had come so far to producing the pure android. Every one of them was plastic hand-molded and of course they were equipped with rationaloid circuits. They had to be to ferry those big cargoes back and forth from the rock belt to Frisco. As rationaloids, Minor Planets had to pay them wages under California law, but I'll bet it wasn't half what the company would have to pay human pilots for doing the same thing. In a couple of weeks' time maybe five servos made stopovers. We kept a close watch on them from the minute they signed the register to the time they took off again, but they all behaved themselves. Operating on a round-robot basis the way they did, it would take us a while to check all of them because Minor Planets employed about forty all told. Well, about a month before the Jovian Moons rush started we got some action. I'd slipped into a spacesuit and was doing some work on the CO{2} pipes outside the Io when I spotted a ship reversing rockets against the sun. I could tell it was a Minor Planets job by the stubby fins. She jockeyed up to the boom, secured, and then her hatch opened and a husky servo hopped out into the gangplank tube. I caught the gleam of his Minor Planets shoulder patch as he reached back into the ship for something. When he headed for the airlock I spotted the square package clamped tight under his plastic arm.