'This Is Us' ending has everyone running to the store for batteries

Batteries. It’s a simple shopping-list item and an incredibly significant answer to the most important question This Is Us fans have been asking since the very beginning.

How did Jack die???

The episode, titled “Clooney,” began with a flashback scene of Kate asking her mom to take her to the mall to shop for a dress for her school’s winter formal. An elated Rebecca then tells Jack, “Oh, can you remind me to pick up batteries?” In the moment, the reminder seemed very unimportant. Until it came down to the last 10 seconds of the show. The cliffhanger.

What seemed like the very first episode for which we didn’t need an entire box of tissues ended up wrecking viewers’ hearts around the country as Rebecca closed the show by asking Jack, “Hey, babe, did we forget something at the mall?” Jack then responded, “I don’t think so.” The camera then pulled out to a wide shot, ominously locking on the Pearson family home’s smoke detector without, you guessed it, batteries.

And fans on Twitter were totally shaken by the revelation. Here are some of our favorites:

Judging by the preview of next week’s episode, if you’re running out for batteries, you should also stock up on your tissues.

This Is Us airs Tuesdays at 9 p.m. on NBC. Watch clips and full episodes of This Is Us for free on Yahoo View.

Check out This Is Us returning for its winter premiere with an explosive therapy session:

Read more from Yahoo! Entertainment:

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• ‘This Is Us’ brings back a beloved character and makes us cry all over again

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