United Kingdom, Jan. 4 -- Millie Bobby Brown has been "sworn to secrecy" over her Stranger Things character's ending.

The 21-year-old actress portrayed the main character Eleven in the hit sci-fi Netflix series, which reached its grand finale last month, and the show's creators, Matt and Ross Duffer, have revealed she was under strict instructions not to tell anyone her character's fate.

Speaking on the Happy Sad Confused podcast, Matt said: "She's not going to tell you, either.

"Don't waste your time.

"Millie swore herself to secrecy."

The Duffer Brothers only shared whether Eleven lived or died with Millie, meaning her co-stars are none the wiser.

During the podcast appearance, they texted her to remind her not to let on to her ca...