A pair of twins are separated at birth in “The Identical.” (Katherine Bomboy Thornton)

In “The Identical,” out Friday, twin brothers are separated at birth. One goes on to become a musical superstar while the other looks a lot like the one who became a musical superstar. In movies, sometimes twice is nice!

Bob and Walt Tenor: Matt Damon and Greg Kinnear play conjoined twins in “Stuck on You,” meaning between them they have two heads, four arms, four legs, one liver, four Oscar nominations and one win.

Fred and George Weasley: This pair of magical gingers — played by twins Oliver and James Phelps — had some of the funniest moments in the Harry Potter series. They also probably had the saddest, but we’re not going to think about that right now.

Susan Evers and Sharon McKendrick: In the original 1961 “The Parent Trap,” Hayley Mills played twins who were separated in infancy by their divorcing parents because apparently the judge who decided custody was drunk out of his gourd.

Sadie and Rose Shelton and Sadie and Rose Ratliff: Bette Midler and Lily Tomlin play two sets of identical twins who end up paired with the wrong wombmate in “Big Business.” You get two of the funniest women in movies playing four of the funniest characters in movies.

King Louis XiV and Philippe: “The Man in the Iron Mask” offers a lesson in monarchical politics: If the queen mother bears identical-twin Leonardo DiCaprios, make one Leonardo DiCaprio king and lock the other Leonardo DiCaprio in a clanging version of a ski mask.

Read more of Kristen Page-Kirby’s Film Riffs:

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