That's right, you've got to wake up and diffuse this "bomb" by "cutting" one of three colored wires in order to stop the alarm. The alarm will go off at your set time with loud, explosion noises and a colored light flash and will signal which wire you need to cut. Cut the wrong one? The explosions won't stop until you get it right.
We recommend this for people without roommates. That would be a bad idea.
And we also want to warn you that you might not want to take this one as carry on to wake you up from your nap on your international flight. That's a really bad idea.