That Wasn't Here a Minute Ago

It was vital that we stole the government secret. I stood outside the complex, waiting. Patrick had told me that he’d invented a sure-fire way of infiltrating the foreign embassy.
“Hey!”
I turned around. Nothing there.
“Psst!”
I surveyed my surroundings, heart thumping frantically. Nothing there.
“It’s Patrick. I’m right in front of you. But – I’m invisible!”

He didn’t explain much, but I don’t blame him. Spies like to keep things to themselves. So when he gave me a petite glass bottle and told me to drink up, I didn’t argue.

Putrid taste on my tongue. Burning in my throat. Tingling in my legs, arms, torso. I looked down. And saw nothing.

Some officials appeared. Patrick told me to follow them, and I obeyed. Sneaking in was easy, eavesdropping was simple. We walked through long corridors, then outside into a courtyard.
“Now, I don’t want anyone to hear this. OK?” one of them said. His companions nodded, and two guards fiddled with their guns. Gulp.
“This is the most important military secret ever. OK?”
They nodded again. “Oh damn, it’s raining. Let’s get this done quickly,” another added.
BANG!

They started, and a bird fled, squawking madly.
“Could have had a tape recorder on it,” explained the guard, reloading his gun. Suddenly, I felt a tingling sensation. Oh no. I tried to sneak away, but they heard my footsteps. I could see a faint outline of my feet. The sensation intensified. Two guns were pointed in my direction.
“Hey,” said one of the guards. “That wasn’t here a minute ago.”