The Twilight Zone, Season 2

Narrator:
These are the invaders, the tiny beings from the tiny place called Earth, who would take the giant step across the sky to the question marks that sparkle and beckon from the vastness of the universe only to be imagined. The invaders, who found out that a one-way ticket to the stars beyond has the ultimate price tag. And we have just seen it entered in a ledger that covers all the transactions of the universe, a bill stamped 'paid in full,' and to be found, on file, in the Twilight Zone.