Almost. I work in a museum at the front desk. The desk was shaped in an L shape, so if you were in the museum shop part, you could see the cash register, which was in the corner, but not the entrance door.

I was organizing the shop a bit, and I heard the desk door open and close. I thought it was just my colleague, but still I kept an eye on the cash register. Usually if a colleague would come in the desk area, he would check around the corner to see if there's any of his colleagues. That didn't happen this time. So, being a good colleague I decided to take matters in my own hand, and walk around the corner to greet my colleague. However, the man I saw, was not my colleague, and he was going through my bag which I kept my lunch in, and a book for if it turned out to be a slow day. I asked him what he was doing, and he replied - visibly shocked- "Ehh, where are the toilets?" Now I'm not a big dude. At the time I was 17 years old and scrawny as fuck, so I thought to myself I can't throw this dude out. I just pointed him to the toilets, hoping he would go away, which he did.

Right after he left, I called my colleague over the walkie-talkies we had, he was outside at our museum's tour boat. As I called him and told him what happened, the alarm of the museum went off. (That basically means the back door has opened, which it shouldn't.) I urged my colleague to come back to the museum so he could turn the alarm off - I wasn't leaving the cash register and my bag alone after that dude came in. Between me asking my colleague to come back and him actually getting to the museum, some visitors came. The alarm was still sounding and it was loud as fuck. I decided to have the visitors wait for a minute until my colleague came back.

My colleague came back, turned the alarm off, and came to the desk area. I gave him a description of the man and he walked around the museum to see if he could find him. He couldn't find him, it turned out the man had fled through the back door, triggering the alarm.

Luckily, he didn't steal my lunch. It was delicious.