-- Have you noticed? Two films, "Rough Night" and "Girls Trip," which hit the box office just weeks apart, are essentially the same film -- though their opening weekend earnings were dramatically different.
"Rough Night" opened at the box office last month with a disappointing $8 million, Box Office Mojo reported. Meanwhile, "Girls Trip," which opened Friday, landed at No. 2 at the box office, earning $31.2 million, according to Box Office Mojo.
Both are cousins of "The Hangover" franchise, where a group of women -- instead of men -- hit the road for some wild and crazy fun.
"Rough Night" follows the mostly white cast as they celebrate at a bachelorette party that ends in an unexpected death. Meanwhile, "Girls Trip" is a bit lighter and follows a mostly black cast as they trek to the Essence Music Festival in New Orleans.
While the stars of "Rough Night" were featured on the cover of Cosmopolitan and Elle magazine, whose readers include a higher percentage of white women, the stars of "Girls Trip" graced the cover of Essence magazine, marketed primarily to black women.
Still, both films got equal promotional footing on the small screen with the stars from both films featured on late-night shows, such as "Watch What Happens Live with Andy Cohen," "The Tonight Show With Jimmy Fallon," and "Jimmy Kimmel Live!"
Gil Roberson, president and co-founder of the African American Film Critics Association told ABC News, however, that Universal likely expected "Girls Trip" to "actually have some crossover."
"Of course there’s a history with [producer] Will Packer with 'Think Like a Man' 1 and 2," he added. "Both of them enjoyed crossover audiences."
The film critic points to Queen Latifah and Jada Pinkett Smith, in particular, who have what he calls, a "crossover profile." He added, "For 'Rough Night' it seems the expectation for crossover may be a little bit lower."
That may explain the film's weak opening weekend last month. ("Rough Night" has since gone on to gross $37 million worldwide, according to Box Office Mojo.)
Roberson notes that both films are being marketed directly to women. It's a strategy that the critic calls smart for several reasons.
"Women make up the majority of [moviegoers] to begin with, so it’s a shame that more films don’t cater directly to them," he explained. "This is the summer of women."
"'Wonder Woman' opened so big and certainly if one or both of these films perform well you might be able to make an argument for that, which is a good thing," Roberson added.
"Rough Night" and "Girls Trip" are an example of what Hollywood calls "twin films," or films with very similar plots that are released around the same time.
"This kind of thing happens a lot," Walt Hickey, Chief Culture Writer for ESPN's Five Thirty Eight told ABC News. "So you have 'Rough Night' from Columbia pictures and you have 'Girls Trip' from Universal pictures, and so these are two totally separate companies, two totally separate productions, two totally separate production teams. And you have ask yourself, 'How the heck does this happen?'"
"They certainly know," Roberson said of the films' studios. "Obviously they study each others release schedules like the Bible so they’re certainly aware of it."
Hickey added, "It's a small town, all things considered, so ideas that are good will oftentimes get pitched in certain directions...it seems like it's just an organic situation. Now we have two different movies with remarkably similar plots."
"Rough Night" and "Girls Trip" are far from the first twin films. The trend actually dates back to the 1930s when "Gone with the Wind" came out around the same time as "Jezebel." Both films center on southern women during the Civil War.
We've also seen this phenomenon with films such as "Back to the Future" and "Peggy Sue Got Married," "Top Gun" and "Iron Eagle," "Dante's Peak" and "Volcano," along with "Antz" and "A Bug's Life."
"Twin films are a pretty stable trope," Hickey said, "and we're going to get more of that because as studios try to ... make sure that they can have a consistent winner, then we're going to start seeing more of these."