The hit Netflix series teased fans once again with a new trailer titled "Eleven, are you listening?" that appears to focus on the back story of Eleven, played by Millie Bobby Brown.

Fans of "Stranger Things" panicked all over social media this morning when a teaser of the show's 4th season was released. The second trailer gave us a glimpes of Eleven's past when Dr. Martin Brenner, played by Matthew Modine, was still alive. The video was set at the Hawkins National Laboratory's "Rainbow Room" where Dr. Brenner ran down experiments and even trained children with special abilities or "super powers". (Watch the full teaser below)

The trailer showed a number of children wearing gowns and shaved head playing with toys that challenges mental abilities. In the end of the teaser, the shot focuses in front of a door with the number 11 on it, and Dr. Brenner can be heard saying "Are you listening, Eleven?"

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Clues from the trailer

The teaser released may be a minute and ten seconds long but it gave fans enough clues to have an idea what the next season will all be about. Since the trailer was upload, a lot of Youtubers and movie fans had already covered and pointed out the so-called easter eggs from the video released. One particular Youtube channel called ScreenCrush stated theories on what possible scenarios will be seen in the next season.

According to ScreenCrush, the next season was rumored to be partially based on the comic book "Stranger Things: Six" which gives a lot of information about "Rainbow Room"

The Youtuber noticed a clip from the trailer a handful of glitching televisions which appears to flash a very significant toy that the flashback of the character Kali, played by Linnea Berthelsen, was playing in the past season, this gave us a clue about Kali's origin, the teaser may also be the day Kali escaped the laboratory.

Another clue they pointed out are the clip where the camera pans throughout the room showing doors with the number 7, 9, and 10, the numbers signifies characters that wasn't shown in past seasons.

It's been 15 months after "Stranger Things" released its first trailer for Season 4, this had fans wonder when the next season will be released. On the first trailer, uploaded on Valentine's day 2020, Hopper, played by David Harbour, returns after his character was feared to have died during the emotional finale of Season 3. (See the first teaser below)

The release date for the anticipated season wasn't confirmed yet. The show delayed its production because of the global pandemic but it is rumored that they recently continued to film the rest of the episodes.

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