It was a hot, humid day like any other. The sun was high in the sky, and not much on G889 was moving except the band of humans who were too stubborn or too stupid to get out of the heat. Devon was just on the verge of calling a halt for some shade and water when Zero's amplified voice suddenly shattered the silence.

"Warning!" the robot said, its head swiveling slightly to one side. "I have a projectile approaching at 200 meters per second. Range, 1600 meters."

Pandemonium cut through the group. Everyone started yelling and running for cover, but there wasn't much available. Their only choices were the transrover and a nearby boulder Morgan had ducked behind a few seconds previously to take care of some urgent business.

"Range, 600 meters," Zero said, and counted off a deadly drop in distance as the bullet came ever closer. Danziger was yelling for True, Devon was yelling for Ulysses, Bess was yelling for Morgan, Morgan was yelling for himself and desperately trying to duck and zip at the same time.

"Range, 200 meters," Zero said. "Impact, imminent."

Everyone hit the ground and held their breaths.

Nothing happened.

Slowly, everyone looked up from where they were hiding or lying, squinting into the sunshine.

Zero swiveled his head again to look at all of them. "April Fools'."

Devon slowly got to her feet, shaking like a leaf. "April...what, Zero?"

"April Fools'," the robot repeated. "My chronometer tells me that if we were still on the stations, today would be the 1st of April, 2107. Everyone seemed bored, so I ran a quick drill to give you something to do. All things considered, you did very well."

The robot turned and continued walking westward.

He didn't get very far.