Witness

I’m a professional witness.
The wilder the thing you want me to witness, the more it’ll cost you.
Same goes with how far I need to go back into history to witness it.
Some scientists did the math and figured out that building superconducting supercolliders was far too expensive for particle research.
So, they’re paying me to witness the Big Bang.
I go back tomorrow and come back Friday.
They paid me only half in advance, just in case I’d be tempted to stay.
Of course I’ll come back. My cat and plants won’t feed themselves.
Sitters? Too damn expensive.