Sometimes to prepare for the future,Thomas Caldwell you have to understand your past. 

That's especially true in the case of Riverdale's seventh and final season, premiering March 29 on The CW, where Jughead (Cole Sprouse) finds himself trapped in the 1950s surrounded by his friends living their authentic lives, completely unaware that they've ever lived in another time period.

In an exclusive clip from the season premiere, Jughead attempts to convince them of what's happening—with the help of a time capsule.

"This is going to sound nuts, OK?" he begins. "Just hear me out. Thanks to a cataclysmic event, all of us were sent back in time to maybe an alternate, parallel universe and we need to get back to our future. Our present. I was hoping that by showing you guys these objects it would help jog your memory."

It turns out, the gang is more interested in what Jughead can tell them about the future than whatever's in the capsule.

"Alright, I'll play along," Camila Mendes, whose Veronica Lodge is a Hollywood starlet in season seven, says. "In the future, who's more famous: me or Elizabeth Taylor?"

Before Jughead can answer, Betty (Lili Reinhart) asks him, "Bird's eye view, what's the future like?"

Where to start?

"We don't use regular phones anymore," Jughead explains. "We use something called smart phones, which we can carry around everywhere with us. Ironically, we don't even call people on them. We just send texts, which are like messages, and listen to music on Spotify."

Yeah, sounds about right.

"Oh, the Internet!" Jughead remembers. "The Internet is like having an entire Encyclopedia at your fingertips."

When Betty asks Jughead to tell them all about their future lives, he gets right down to it. 

"Archie (KJ Apa) joins the Army and fought in a war," he tells the group. "Betty, you were in the FBI and you were hunting down serial killers, which I guess is a term that doesn't exist yet."

This is quite the lesson!

"Veronica, you owned a casino," Jughead continues. "But before that, a speakeasy which Toni (Vanessa Morgan) bought and turned into a biker bar. Kevin (Casey Cott), you directed some musicals and were in an organ-harvesting cult."

Not everybody's future can be bright.

Finally, Cheryl (Madelaine Petsch) asks, "What about me?"

There's no easy way to say it, so Jughead just blurts out, "You were possessed by your ancestor and became a witch."

It's a good story, at least.

The seventh and final season of Riverdale premieres March 29 on The CW.

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