Lively also thanked Spears in the credits.

Britney Spears' influence on pop culture goes on and on.

“It should be in the Smithsonian or the Met.

Blake Lively wore a Britney Spears dress

Blake Lively wore Britney Spears' Versace dress.John Nacion/Variety via Getty; Fairchild Archive/Penske Media via Getty

But it’s on me.

I feel so lucky!”

“This dress meant so much to me because of what she meant to me,” Lively said.

The film is an adaptation of author Colleen Hoover’s popular 2016 novelIt Ends With Us.

Then a former flame, Atlas (Brandon Sklenar), reappears in her life.

The romance arrives in theaters Friday, Aug. 9.