Back in the 1940s, "The Philadelphia Story," Katherine Hepburn set the bar for fiery feminism as a society girl choosing between two beaus, Cary Grant and James Strewart. 

The 1971 cult hit "Harold and Maude" is the best movie about an affair between a suicidal teen and an 80-year-old woman ever made, thanks to Ruth Gordon and Bud Cort.  

Woody Allen's witty and bittersweet "Annie Hall," which he directed and starred in with Diane Keaton, won the Best Picture Oscar and would perfect for a 1977 time capsule.

In the John Landis-directed 1988 hit "Coming to America," Eddie Murphy taught us -- hilariously -- to love whomever we want, just do it for the right reasons. 

Rob Reiner's 1989 hit "When Harry Met Sally" is still remembered for Billy Crystal and Meg Ryan's iconic deli scene that prompted the line "I'll have what she's having" to be repeated by millions of movie-goers.

Julia Roberts and Richard Gere were a prostitute and a businessman in the iconic Cinderella story, "Pretty Woman," and the 1990 R-rated romance raked in $460 million at the worldwide box office for Disney.

Andie MacDowell turns jaded weatherman Bill Murray around ... and around and around in 1993's "Groundhog Day." It only grossed $70 million for Columbia but became a huge home entertainment hit. 

Without Ben Stiller's burning love for Cameron Diaz, the Farrelly brothers' 1998 hit "There's Something About Mary" would have been just a $390 million-grossing gross-out flick. 

Richard Curtis' followup to "Four Weddings and a Funeral" saw travel bookshop owner Hugh Grant woo Hollywood superstar Julia Roberts in the hip London neighborhood of "Notting Hill." The 1999 British comedy won over moviegoers on both sides of the Atlantic and earned a worldwide gross of $364 million.

Mel Gibson got more than he bargained for when he started reading the mind of Helen Hunt and other females in "What Women Want." So did Paramount, when the 2000 film took in $182 million domestically and $191 million abroad.

Renée Zellweger had a tougher time loving herself than her two beaus in "Bridget Jones's Diary," which grossed $218 million globally in 2001.

Nia Vardalos and John Corbett had Americans going "opa!" in 2002 as "My Big Fat Greek Wedding" took in $241 million domestically for IFC Films, which is still tops for both an indie film and a rom-com. 

Katherine Heigl and Seth Rogen were a very odd couple in Judd Apatow's 2007 raunchy comedy hit "Knocked Up," which made $219 million at the box office. 

Sarah Jessica Parker finally landed Mr. Big in the 2009 "Sex and the City" movie, and New Line joined in the celebration after bagging $415 million at the box office. 

Jennifer Lawrence and Bradley Cooper fought mental illness and themselves to find love in David O. Russell's "Silver Linings Playbook," which grossed $236 million in 2012 for The Weinstein Company.

Battling the too-friendly frat boys next door strengthens the bond between Rose Byrne and Seth Rogen in "Neighbors," which took in $270 million worldwide in 2014. 

"Trainwreck" put Amy Schumer's career on the fast track with its $110 million breakout at the box office in 2015.