In The Offera limited series about the making of The Godfather on Paramount+, Justin Chambers makes an appearance as Marlon Brando, a cinematic titan that would be difficult to embody without descending into caricature. Chambers wisely doesn't draw inspiration from the many parodies that exist of the Corleone patriarch, nor from Brando's own preference for method acting, instead choosing to deliver a subdued and authentic portrayal of the actor.

Portraying a fellow actor can often come across as a hollow impression (which is probably why they're attempted infrequently), but the best performances humanize figures that have both public and private personas. Far from merely impersonating them, they seek to make them relatable by finding their hidden truths, showing them to be multi-faceted, and above all, reminding fans that they are real people.

Johnny Depp - Ed Wood (Ed Wood)

Johnny Depp as Ed Wood in a dressing room

Ed Wood was by all accounts a strange and eccentric director and actor, so it only makes sense that Johnny Depp, known for making strange and eccentric films like Edward Scissorhands, would collaborate with Tim Burton once again to portray the Hollywood outcast at his most prolific.

RELATED: Ed Wood’s 10 Greatest Movies (According To IMDb)

Wood loved his movies so much that he starred in many of them, and is particularly known for playing both roles in Glen and Glenda. Depp is full of vigor, bravado, and warmth in Ed Wood as a man happy to make offbeat exploitation films, treating Wood's B and C-level movies like Academy Award-winning masterpieces. Loving his own films with the ardor he did, no doubt the real Ed Wood would have been proud.

Robert Downey Jr. - Charlie Chaplin (Chaplin)

Robert Downey Jr as Charlie Chaplin in his little tramp costume in Chaplin

Robert Downey Jr. has become one of several actors inseparable from the characters they played, but long before he was Tony Stark he was Charles Chaplin. With his bowler hat and whimsical waddle, he was the spitting image of the Little Tramp, one of Chaplin's most famous characters, and as well-known as Batman or Mickey Mouse.

Chaplin chooses to emphasize more of the titular character's raucous lifestyle and sex life than his filmmaking, but Downey's performance remains grounded and vulnerable. It may be hard to believe that at one point in the '20s and '30s Chaplin was a global megastar, but after watching Downey channel his trademark energy into Chaplin's best-known routines, it's not hard to see why.

Renée Zellweger - Judy Garland (Judy)

Renee Zellweger as Judy Garland in Judy

Judy Garland is most often associated with The Wizard of Oz or more specifically her doe-eyed youth, but Judy gives Renée Zellweger the opportunity to remind fans that Garland was in fact a whole person, a strong singer, and a powerful woman, even if the industry tried to deny it.

Zellweger honors Garland's legacy by making sure to convey her trials and tribulations as well as her triumphs, allowing her to emerge as a performer who struggled to take control of her own narrative but refused to give up trying. Zellweger received the Academy Award for Best Actress for this inspiring performance.

Jim Carrey - Andy Kaufman (Man On The Moon)

Jim Carrey as Andy Kaufman on stage in Man on the Moon

Rarely have Jim Carrey's gifts for the absurd, the unexpected, and the earnest been so superbly combined than in Man on the Moon, where the comedian played Andy Kaufman. Kaufman, like Carrey, was an actor, comedian, and performance artist, and his talents even extended into professional wrestling on occasion.

RELATED: Jim Carrey's 10 Best Movies, According To Metacritic

The movie follows the king of cringe humor through his childhood, standup days, and beyond, giving Carrey a lot of material to work with. He has the creative bandwidth to go all in, taking Kaufman's work seriously, including the gags he was known to play on co-stars of Saturday Night Live and Taxi. 

Martin Landau - Bela Lugosi (Ed Wood)

Bela Lugosi sitting on a chair and frowning in Ed Wood.

Bela Lugosi's version of Dracula has long been regarded as the best nearly a century after he first put the cape on, but in his later years, the horror icon was remembered only for his drug use. Ed Wood still thought Lugosi was a star, though, even as he struggled, and Martin Landau's performance as Lugusoi in Ed Wood reminds movie audiences why.

Opposite Depp's spirited Wood, Landau's decrepit star does not burn anywhere near as brightly, but he imbues Lugosi with reverence and dignity. He's careful to show how much Wood's sincerity and kind words transform Lugosi on screen, as though to express just how much a person's belief in someone else can mean the difference between life and death.

Ben Affleck - George Reeves (Hollywoodland)

George Reeves (Ben Affleck) flying on wires in Hollywoodland

Before there was Christopher Reeve, George Reeves donned the red and blue suit to portray Superman for the Adventures of Superman. Though he might not be considered one of the best Superman actors, the series was a beloved fixture of '50s television until Reeves died under mysterious circumstances in 1959. Hollywoodland explores his death, and though he was thought to have taken his own life, he was more than likely murdered.

Ben Affleck, who bears a striking resemblance to Reeves in both face and frame, performs double duty as Reeves and, in flashback clips, the Man of Steel himself. He also shows the conflict between the superhero and the man behind the suit, as well as the studio puppet and the hopeful movie star, letting audiences draw their own conclusion of whether or not depression — or someone else — was responsible for his death.

Cate Blanchett - Katharine Hepburn (The Aviator)

Katharine Hepburn sits and looks to her side in The Aviator.

There were few people who could get away with bossing millionaire Howard Hughes around, but in The Aviatorthat person is Katharine Hepburn, played with aplomb by Cate Blanchett. Hepburn has been parodied before in her later years, but it's delightful to see her here as a young, confident, and brazen equal to Hughes as he sought greater heights in the Hollywood studios and then in the air.

RELATED: Martin Scorsese's 7 Most Interesting Biopic Subjects, Ranked

There are lots of celebrities playing celebrities in the movie (Gwen Stefani plays Jean Harlow at one point), but Blanchett shows the most authenticity. Her north star is the fact that Hepburn cared about what happened to Hughes, even as she saw the darkness closing in on him, and it gives Blanchett's performance depth.

Margot Robbie - Sharon Tate (Once Upon A Time In Hollywood)

Margot Robbie as Sharon Tate in Once Upon A Time In Hollywood

Once Upon a Time in Hollywood is one of the best movies where actors play actors, but surrounding the fictional performers played by Brad Pitt and Leonardo DiCaprio is a whole cast of talent embodying stars of the '70s, like Bruce Lee and Sharon Tate.

It's Margot Robbie's turn as Sharon Tate that really shines, especially since the real Tate's life was cut so tragically short, robbing the world of any more films starring the likable blonde. But Robbie's role, while not a large one, is fully realized and fleshed-out, and helped by Quentin Tarantino's revisionist ending.

Michelle Williams - Marilyn Monroe (My Week With Marilyn)

Michelle Williams in My Week with Marilyn

Did the world ever really know Marilyn Monroe? There were so many versions of her, in her films, on the red carpet, and in her private life that it's hard to be sure, especially for a Hollywood icon. But Michelle Williams provides the best glimpse of all Monroe's facets in My Week with Marilyn, about a young production assistant who enjoys a week with her in the English countryside while she films The Prince and the Showgirl.

Not only does Williams get the broad strokes right by singing, dancing, and strutting her stuff in sequin gowns, but she also gets the little details correct, like understanding that Monroe had one voice for the movies and one for her everyday life. Monroe's private moments weren't captured on film, so Williams must do the best she can to approximate them, and she does more than that; she gives Monroe a vessel to expand herself.

Jason Scott Lee - Bruce Lee (Dragon: The Bruce Lee Story)

Jason Scott Lee as Bruce Lee in Dragon: The Bruce Lee Story

Released the same year that news broke of Brandon Lee's death, Dragon: The Bruce Lee Story follows the meteoric rise of Brandon's father Bruce Lee, the martial arts superstar that had just transitioned from Hong Kong to Hollywood before passing away under mysterious circumstances.

As Lee, Jason Scott Lee not only gets all of the star's gravity-defying moves down, but he also infuses him with the humor and the daring fashion sense that Bruce Lee was known for. Lee's zest for life offscreen is what made him such a joy to watch onscreen, and this Lee's performance will make fans miss Little Dragon even more.

NEXT: 10 Best Performances Where Actors Played Fictional Versions Of Themselves