This happened to me years ago. I was put in an empty office at the opposite end from my boss, and because he couldn't walk up behind me to see me working, he secretly installed a program on my computer that took a screenshot every 30 seconds (or so?).
I quickly noticed that my computer was hitching regularly (when the screenshot was taken - this was in the late 90s BTW), and so investigated my computer on a day when he wasn't in the office.
After finding what looked like malware on my computer, I checked with other colleagues - and the other owner - and no one had any idea what it was.
So we put the office network on lockdown, halted everything and started the process of rotating all our passwords and scanning every computer in the office looking for signs of intrusion, etc..
We lost a solid day of productivity for everyone, and when we finally reached the other boss, he owned up to what he had done, and the other owner - who had spent the day in a panic - wasn't thrilled about it to say the least.
The irony was that I was probably the most productive person in that office (in my humble opinion).
I quickly noticed that my computer was hitching regularly (when the screenshot was taken - this was in the late 90s BTW), and so investigated my computer on a day when he wasn't in the office.
After finding what looked like malware on my computer, I checked with other colleagues - and the other owner - and no one had any idea what it was.
So we put the office network on lockdown, halted everything and started the process of rotating all our passwords and scanning every computer in the office looking for signs of intrusion, etc..
We lost a solid day of productivity for everyone, and when we finally reached the other boss, he owned up to what he had done, and the other owner - who had spent the day in a panic - wasn't thrilled about it to say the least.
The irony was that I was probably the most productive person in that office (in my humble opinion).