The Missing Mechanical Parts

Lately we've been experiencing a weird phenomenon where the machinery parts have been disappearing. We cannot operate the factory without the parts, so ... can you help us solve this case? You'll be well-rewarded for your work here.

Thank you. From the investigation we have conducted ourselves, the missing parts can be construed as a stranger walking into our factory and proceeding to hide the item somewhere. The parts need to be here so the factory can be run...should we go to where the parts are hidden as?

Is that right? I guess you're busy granting favors from a lot of people. But if you feel a change of heart, we're ready to listen.