Set Your Flux Capacitor for ‘Back to the Future' Day

Movie trivia time: How exactly do you get to Doc Brown's house?

If you're in the year 1985, you'll want to ride your skateboard over to the gentleman's abode, which will be crammed with clocks, Einstein's overflowing dog bowl, and one very large speaker.

But if the year happens to be 1955, and you're still in 1985? You're going to need a tricked-out DeLorean and a flux capacitor installed in the car's dashboard.

Of course, if you're near Pasadena, and the year is 2020, you only need to make for 4 Westmoreland Place, which is where the Gamble House is located.

The esteemed Greene & Greene landmark, which was built for an heir to the Procter & Gamble company well over a century ago, did indeed serve as Doc Brown's 1955 manse, the very place where the flux capacitor, the good doctor's amazing time-travel device, was invented.

And to celebrate "Back to the Future" Day, which falls on Oct. 21 whatever year you happen to be visiting?

You can re-watch the movie, rock a puffy vest, or make for the Gamble House Bookstore to buy your very own "The Future Hasn't Been Written Yet" t-shirt.

It's an insider-y piece of apparel, one that pays homage to the real house's fictional starring role.

But before you turn your DeLorean in the direction of Pasadena, do order your t-shirt ahead of time on the bookstore's site. Just be sure to select "pick-up," if you intend to stop by and gather your garb there (there is a delivery option, too).

The t-shirt is $25. And here's something to shout "Great Scott!" over: All of the purchase price goes to supporting the Gamble House.

As the full script seen on the front of the shirt?

"The Future Hasn't Been Written Yet So Let's Make It a Good One" is just below an illustration of Marty McFly approaching the house, with the words the "The Gamble House" printed near the bottom of the tee.

Of course, you'll want to wear your t-shirt on Oct. 21 and any other day of the year, especially if you're eager to express your BTTF fandom.

So why does the 21st day of October get the BTTF spotlight? Marty and Doc traveled to the future on Oct. 21, 2015 in the second film in the series.

But if you live in Southern California, you can visit one of the most famous locations in any of the films at any time, just by making for the Crown City.

The interior spaces at The Gamble House are closed right now, but there is a Gardens & Gables tour which provides guests plenty of looking-around opportunities just outside the beautiful Craftsman structure.

And something fun if you're going to get super film-deep about calling upon the Gamble House Bookstore to pick up your t-shirt?

The small and handsome outbuilding, which sits just north of the house, is where Doc Brown's workshop was located in the movie, which means your t-shirt will be waiting at the very spot where the scientist first tinkered with time travel.

Heavy.