It is the third chapter in the film franchise based on E.L. James' "Fifty Shades" novels.
"Expanding upon events set in motion in 2015 and 2017's blockbuster films that grossed almost $950 million globally, the new installment arrives for Valentine's Day 2018," said a message accompanying Sunday's one-minute clip.
The preview, which has already gotten more than 1.5 million views since it was posted, shows Christian and Anastasia getting married and Anastasia adjusting to her new lifestyle.
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