Ben and Gwen are 17, Kevin is 18, Grandpa Max is... really old.

DISCLAIMER: I do not own Ben 10, Alien Force, or Ultimate Alien, but if I did, I would be rich! Jetstream is owned by... well check my account page to see who made him. I have a link set up there.

"JetStream!" the teenager called out. There was a flash of green light and a sudden explosion of blue smoke.

For a moment, nothing happened. Then, a blur of white and blue shot out from the fog, zooming towards the winged creatures that hovered 20 feet above the ground. They had gray, slightly transparent wings like a grasshopper's, scaly black skin, clawed hands and feet, with hollow faces and dark blue eyes.

JetStream held out his right palm and a jet of icy cold wind sprayed from a large blue tube that extended from his back all the way down to his hand. About 6 of the black aliens fell to the floor, completely immobile. Grinning to himself, JetStream held out his palm again, ready to blast once more, but he was suddenly pulled downwards as one of the clawed hands of a Zerax grabbed hold of his leg. It slammed him down into the concrete, cackling evilly.

"Hey!"

A large, pink hand stretched out from the behind the sprawled out body of Ben and headed straight towards the remaining Zerax (plural). The energy-hand clamped around the waists of a handful of Zerax and they all gagged horribly, coughing up thick green goo, presumably blood.

Gwen Tennyson put her hands on her hips, her long orange hair flowing in the breeze. "No one messes with Ben but ME!"

"And me!" called a voice. Kevin Levin was running down the road, running his hand across the black concrete. His whole body was slowly beginning to turn solid black, as if someone had just dumped a bucket of paint over his head. His hand morphed into a giant hammer and he smashed it into a bunch of Zerax, sending them flying.

Ben Tennyson, who had come to his senses jumped up from the giant crater that he had made and slammed down on the Ultimatrix again. There was a flash of green, and a deep, rumbling voice erupted from the spot where he had just been.

"Humongousaur!"

The giant, dinosaur-like alien swished it's brown tail and more Zerax went flying, coughing up the same strange green goo. Ben grabbed 2 Zerax off the floor and put them up to his face. "Revenge is SWEET!"

Within 10 seconds, there were no more Zerax in sight, and Ben was back to normal rubbing the back of his head and grinning. "Ben 10 saves the day again!"

Kevin coughed, which was most likely a lame cover-up for a laugh. Gwen rolled her eyes and muttered something that sounded a lot like, "dweeb."

"Well," said Kevin, shoving his hands into his pocket and looking over at his car. "You two should probably get-"

Suddenly, there was a violent explosion, and the three teens were thrown back. Kevin slammed into the side door of his car and he groaned loudly.

"The date... what's the date?"

The voice came from a man. A man that was crouched on the floor, a wild look in his dark eyes. His black hair was a wild mess, and his usually white suit was dirty and torn in several places.

"Professor Paradox?" Gwen cried out. She got up and looked down at the Professor with a look of sorrow in her green eyes.

Professor Paradox shuddered violently and his body fizzed, as if he was just a hologram that was having static. Just to be sure, Gwen reached down and touched him. He was very much solid, so what was wrong?

The Professor looked straight at Gwen and repeated, "The date... what's the date?"

The three teens were now standing around the Professor. Ben crouched down and tried to help the Professor up, but it was as if he weighed ton. Kevin had his arms crossed, which got a disapproving glance from Gwen, but he didn't seem to notice.

"October 7th, 2010," Ben said hurriedly, staring at Professor Paradox.

The Professor cursed under his breath and began to mutter to himself. "Not to late... I should've known... Could be ready..." He looked back up at the teenagers, a psycho-sort-of-smile on his face. "Check on your grandfather, Ben, Gwen."

"Ok, something's seriously wrong with him," Kevin began. "We should-"

Professor Paradox reached up and grabbed onto Ben's green jacket. "BE READY, BOY! BE READY!" he screamed suddenly. Then he was gone.

Ben exchanged glances with Kevin and Gwen. "What the heck was that all about?"