News articles say the U.S. poster features the actors alongside one another. It's not exactly true. Even in the U.S. poster the lone black couple are waaaay further in the background. They're the smallest duo pictured and partially obscured on both sides by the pairs in front.
You can barely see them anyway!
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The U.K. poster also adds a red suitcase in Malin Akerman's hand, kind of in the same place Love and Hawk stand in the U.S. poster. There are flowers in female cast members' hair and a lei around Vince Vaughn's neck in the later version. Cool. The backdrop is more tropical and the water the actors stand in shows up as much a much lighter blue. Wait a second, the couples are posing differently in relation to one another, too. Hmm. So it's not the only difference.
My guess is both posters were heavily edited. And you know what? I think the U.K. one is kind of better as a traditional movie poster.
The people are closer to the viewer and it tells you more about the movie's setting. The U.S. poster gives us more information about who is in the film, but Universal reps said the U.K. poster included those "most recognizable in international markets."
And isn't that true? I'd never heard of Kali Hawk before. It's cool her name was on the U.S. poster, but it sounds pretty reasonable that it was left off the U.K. version. Faizon Love is the one who ought to be mad here.