whatelsecanwedonow:

Back to the Future
Back to the Future (1985) dir.
Robert Zemeckis

This is it! This is the answer

– it says here that a bolt of lightning is
going to strike the clock tower at precisely 10:04 PM, next Saturday
night. If we could somehow harness this lightning, channel it
into the flux capacitor… it just might work. Next Saturday night,
we’re sending you back to the future!