In An Instant (2015)

S6E17 The Long, Long, Long Weekend

Gazoo whisks Fred away to the twenty-first century, making a stop at the Slate Rock and Gravel Company. There, Fred discovers that the interest on a $4.00 loan he borrowed from Mr. Slate has ballooned to over $23 million! After their adventure, Fred is determined to pay off the loan as soon as they return to the Stone Age.