Cher returns to the big screen for the first time in eight years this Friday (July 20), when Mamma Mia 2: Here We Go Again opens in theaters.

The "Believe" songstress plays Ruby Sheridan, the glamorous mom of Donna Sheridan, played by Meryl Streep. She's clearly got the ABBA bug, having announced a new album covering the Swedish supergroups's biggest hits, but there's just one catch: Cher is 72, just three years older than Meryl.

Is that super-pernickety of us? So be it. Here's a list of 11 other age-inappropriate castings that have gotten under our skin.

11. Sean Connery as Harrison Ford's Dad in Indiana Jones and The Last Crusade

1989's The Last Crusade was Indiana Jones's third outing, filmed when Harrison Ford was a spritely 46. In it, he goes looking for the Holy Grail in a bid to rescue his dad, the venerable Professor Henry Jones, Sr., who was played by Sean Connery despite the fact he was only 12 years older.

https://www.youtube.com/watch?v=q0vvYHuA10U

10. Vivian Vance as Lucille Ball's Older Friend in I Love Lucy

Ethel was portrayed as much older than Lucy on the show, but in real life Vivian Vance was just two years older than Lucille Ball.

https://www.youtube.com/watch?v=nmEpAmFrATo

9. Hugh Laurie as Benedict Cumberbatch's Dad in Fortysomething

Hugh Laurie played the titular fortysomething doctor in this British sitcom from 2003, which was appropriate, given he was at the time 43. His son Rory, however, was supposed to be in his late teens, and played by Benedict Cumberbatch, who was 26. It's possible, of course, but Hugh would've had to have been a very youthful 17 when his son was born, and done his medical studies while he was a toddler.

https://www.youtube.com/watch?v=0yfYa_KQwbg&t=32s

8. Toni Collette as Paul Dano's Mother in Little Miss Sunshine

Toni Collette was just 33 when she played Sheryl, the overworked matriarch of the dysfunctional Hoover family in this comedy from 2006. That was young enough to be playing a mother, but things weren't helped when Paul Dano was cast as her teenage son Dwayne: he was, in fact, 21.

https://www.youtube.com/watch?v=VWyH_twcMl0

7. Sally Field as Tom Hanks's Mother in Forrest Gump

Tom Hanks was just 37 when he played his most memorable character, a slow-witted but good-hearted man from Alabama in this 1994 romantic drama. There was just one thing: Sally Field, who played Forrest's mother, was only 10 years older than him.

https://www.youtube.com/watch?v=SqOnkiQRCUU

6. Amy Poehler as Rachel McAdams's Mother in Mean Girls

"You girls keep me young," says cool mom June (Amy Poehler) to her daughter's friends in Tina Fey's 2004 high school comedy. She's right about being young, and not just because she's wearing a pink velour tracksuit, but because she's only seven years older than Rachel McAdams, who plays daughter Regina, a.k.a. "evil in human form."

https://www.youtube.com/watch?v=yEQV2OJVBx4

5. Winona Ryder as Zachary Quinto's Mother in Star Trek

This 2009 movie rebooted the Star Trek franchise by taking us back to a time when the Enterprise crew were still young and untested. Zachary Quinto played Spock, Chris Pine Captain Kirk, Zoe Saldana Uhuru, and Simon Pegg Scotty, but the biggest surprise was Winona Ryder's human character Amanda Grayson: first, she was Spock's mother (he was only half Vulcan, after all), and second, that Winona was just 37 at the time. Zachary was 31.

https://www.youtube.com/watch?v=pKFUZ10Wmbw

4. Angelina Jolie as Colin Farrell's Mum in Alexander

Oliver Stone's 2004 epic about the legendary Alexander the Great didn't exactly set the box office on fire, managing to upset historians and film critics alike. One factual inaccuracy was clear, however, even to lay audiences: while 27-year-old Colin Farrell donned a blond wig to play the Macedonian king, Angelina Jolie, a mere 11 months older, played his mother Queen Olympias. Impressive.

https://www.youtube.com/watch?v=Bh6LKIdxqCU

3. Susan Sarandon as Melissa McCarthy's Grandmother in Tammy

Melissa McCarthy played a middle-aged woman who hits the road after losing her job and discovering her husband has been unfaithful in this 2014 comedy. Melissa was herself 44, which checks out, but 68-year-old Susan Sarandon played her hard-living grandma Pearl, which definitely, categorically, doesn't.

https://www.youtube.com/watch?v=N8d6Bpl2eAo

2. Crispin Glover as Michael J. Fox's Father in Back to the Future

We may allow this one. American Gods star Crispin Glover was actually three years younger than Michael J. Fox when he was cast as his hapless dad George, but the time-traveling narrative makes this a possibility. Teenager Marty McFly goes 30 years into the past, back to when his dad was the same age as him, and not his dad at all. Yet. Except when he is, 30 years in the future, which is also the present. Hmm. Our heads hurt.

https://www.youtube.com/watch?v=95_DB6GgLQs

1. Anne Bancroft as Katharine Ross's Mom in The Graduate

Mrs. Robinson became the poster child for older women everywhere in this classic 1967 film, when she seduces aimless college graduate Benjamin Braddock (Dustin Hoffman), admonishing him with the line, "I am twice your age." So it comes as some surprise that the woman who played her, Anne Bancroft, was just 35 at the time, a mere six years older than Dustin (who was a lot older than his character was supposed to be), and eight years older than her screen daughter Elaine (Katharine Ross).

https://www.youtube.com/watch?v=XxJDOkr_UhE

Can you think of any other examples?