You want to generate buzz when you go guerrilla.

But when it generates 9-1-1 calls to the police, it may not be the attention you were aiming for.

It happened last week at Dell in Texas. Police received calls that a masked gunman was inside the computer company's offices. There was no gunman, but there was a threatening individual dressed like a biker in black ordering people to go to the lobby. The man wasn't out to do any harm, merely herding  people to the lobby as a stunt and an internal promotional event to unveil the new Dell Streak tablet.

The police ended up arresting the masked actor and his supervisor.

When guerrilla marketing goes right, you really stand out as a creative thinker, you go viral, you encourage copycats — it can be a great spectacle.

When guerrilla marketing goes wrong, you really stand out as a creative thinker, you go viral, you encourage copycats — but it can be a great spectacular pain in the ass for those involved.

A quick checklist to avoid needless discomfort:

You can keep the mystery, but don't make it threatening. Post 9/11 has forever changed our thinking. You can't have mysterious boxes lying around or imposing individuals forcing you to do something without expecting repercussions.

Make it easy to find out what's going on. Again, keep the mystery and have your fun, but don't make people wait forever to discover its purpose.

Make sure all of the proper people are in the know. If it's internal, make sure supervisors are aware of some activity going on today. They don't have to know everything, just enough to help others to play along. If it's a risky venture outside of the office, you may still want someone "official" around to make sure things don't get out of hand.

Minimize risk of panic. If a lawsuit is the attention you're seeking, then go for it.

Make sure the reveal is just as big as the build. There is nothing more disappointing than getting people engaged and not living up to their expectations.

Make sure it fits the brand. If spectators can't make the connection between the brand and the "moment," it doesn't do much for the brand. People may talk about that cool stunt in Times Square and never mention who sponsored it. Remember, you want people to talk about your brand.