When you tune in to I Know This Much Is True on HBO this Sunday, no need to adjust your sets: There really are two Mark Ruffalos on your screen.
In the limited series based on the best-selling novel of the same name by Wally Lamb written and directed by Blue Valentine auteur Derek Cianfrance, the Avengers star takes on the intense task of playing identical twins Dominick and Thomas Birdsey in what the network describes as "a family saga that follows their parallel lives in an epic story of betrayal, sacrifice and forgiveness.
While playing two characters in one project sounds difficult enough, Ruffalo's job here also requires him to sensitively tackle the portrayal of severe mental illness as Thomas suffers from paranoid schizophrenia. No easy feat, but if he pulls it off, prepare to hear his name come this year's Emmys. (If they even happen, that is.)
Ruffalo's hardly the first actor who's tackled playing twins, however. In fact, it's become something of a rite of passage in Hollywood. To see all the stars who've come before him, scroll down!
In this 2008 fantasy adventure based on the book series of the same name, the future Good Doctor star played the Grace twins, Jared and Simon.
Paulson's played many different characters over the course of her tenure on Ryan Murphy's anthology, sometimes even within the same installment, but in the fourth, she had the distinction of playing conjoined twins Bette and Dot Tattler.
Before her breakout role on The Killing, Enos appeared on HBO's polygamy drama as twins JoDean and Kathy Marquart.
The SNL vet appeared on the HBO comedy's third season as twins Shane and Cole Gerald.
In this 1992 Hong Kong action-comedy, the legendary martial artist starred as twins separated at birth.
In this 1988 farce loosely based on William Shakespeare's The Comedy of Errors, the icons each starred as a set of identical twins mismatched at birth, with one of each pair growing up in a wealthy urban family and the other in a poor rural family.
In this 1991 action flick, the iconic Belgian actor starred as twins Chad and Alex Wagner.
The High School Musical alum starred as Lady Margaret Delacourt, Duchess of Montenaro and the identical looking baker Stacy DeNovo in Netflix's 2018 update on The Prince and the Pauper, as well as in the forthcoming sequel, The Princess Switch: Switched Again.
For three seasons, the Disaster Artist actor played twins Vincent and Frankie Martino, a bartender and a gambler, respectively, who get embroiled in with the Mob in late '70s-NYC in this HBO drama from The Wire creator David Simon.
The Avengers star will play identical twins Dominick and Thomas Birdsey in this limited-series adaptation of Wally Lamb's novel of the same name from director Derek Cianfrance, premiering on HBO on May 10, 2020.
For much of the CW hit's five-season run, the Israeli actress played both the scheming Petra and her twin sister Anezka.
On this ABC Family series loosely based on the book series of the same name, which aired for two seasons from 2011-13, the As the World Turns alum played identical twins Emma Becker and Sutton Mercer who discover one another as teenagers after being separated at birth.
In the seventh season of the Freeform hit, we learned that Bellisario's Spencer Hastings had an evil twin named Alex Drake and she began pulling double duty.
On this short-lived 2011-12 CW series, the Buffy the Vampire Slayer legend played estranged twins Bridget Kelly and Siobhan Martin.
The Disney star played twins Hallie and Annie in the 1998 remake, leaving '90s kids everywhere asking, "How did they do that?!"
The two-time Golden Globe nominee played onscreen twins Emmit and Ray Stussy in the hit drama series.
The actor portrayed real-life Winklevoss brothers in the 2010 Academy Award-winning film.
The iconic comedian played a total of four characters over the course of three movies; most famously he played estranged twins Austin Powers and Dr. Evil.
The original cast member's first onscreen twin appearance as Pheobe and Ursula Buffay took place in the 1995 episode "The One With Two Parts, Part 1."
The nine-time People's Choice Award winner played fraternal twins Jack and Jill in the 2011 holiday comedy.
With help from body doubles Emmy Buckner and Shelby Wulfert, Cameron pulled double duty as brainy basketball star Maddie and girly teen star Liv in the Disney Channel series.
The actress played CIA and FBI agent twins Nimah and Raina Amin in ABC's hit drama series.
Eighteen years before winning the Oscar for Best Actor in a Leading Role, Leonardo played twins King Louis and Phillippe in the 1998 drama.
The Golden Globe-winning played George and Oscar Bluth in the Fox/Netflix sitcom.
The actor picked up a Golden Globe and an Oscar nomination for his work as playing Charlie and Donald Kaufman in the 2002 film.
The star portrayed Alred and Frederick Borden in the 2006 Academy Award-nominated film.
The Golden Globe winner played lead twins Bill and Brady Kincaid in the 2009 picture.
The actor took home a British Independent Film Award for his work as gangsters Reggie and Ron Kray in the 2015 crime indie.
The New York native played Paul and Eli Sunday in the 2007 Oscar-winning film.
The former Saturday Night Live star played estranged twins Kevin Pope and Jake Hayes in the 2002 action comedy.
I Know This Much Is True premieres Sunday, May 10 at 9 p.m. on HBO.