1 | Alec Guinness
Kind Hearts and Coronets
Suggested by verbalrob, meekstom 21, Sceptic101 and Alexander Simon
Many readers would have included the actor’s performance in the Ealing Studios black comedy Kind Hearts and Coronets, a film “best known now as an early showcase for Alec Guinness”, according to Liese Spencer, writing for the Guardian in 2011. In the film, Guinness plays eight different characters belonging to the same aristocratic D’Ascoyne family, quickly transforming from suffragette to admiral, from man to woman, from young to old man, often disappearing behind layers of makeup and dress.

2 | Daniel Day-Lewis
My Left Foot
Suggested by Richard Paige, Nepthsolem, overrated and Telvannah
“My Left Foot is a special favourite of mine,” writes Telvannah, adding that the actor “has made some absolutely astounding movies where his change was beyond belief”. In the film, Day-Lewis plays an Irish writer and artist with cerebral palsy. Reportedly, the actor spent the entire shoot being fed and carried around in a wheelchair. “The transformative genius of Day-Lewis is such that it wouldn’t surprise me at all if it later emerges that it was in fact him playing at least four of the roles cited [in your list],” concludes reader overrated.

3 | John Hurt
The Elephant Man
Suggested by Stuart Basson, chephren, AbFalsoQuodLibet, leuan, Yossarianspal, Quicknstraight
“Where’s Oscar winner John Hurt’s Elephant Man?” asks Yossarianspal, echoing many of our readers, who were expecting to see the British actor’s famous metamorphosis into Joseph Merrick, the Victorian Englishman whose physical deformities took him from sideshow circuit to high society, to be featured in our list. “No CGI, either – straight makeup and prosthetics that took many hours to apply every day,” explains chephren. But “it wasn’t just the prosthetics”, adds AbFalsoQuodLibet, “it was everything, including [his] voice”.

4 | Cameron Diaz
Being John Malkovich
Suggested by ts808 and Yosserian
“Cameron Diaz in Being John Malkovich surprised me,” shares ts808. “I had no idea it was her until afterwards,” agrees Yosserian. In Spike Jonze’s 1999 film, Diaz is barely recognisable, with brown contact lenses, plain makeup and an uncontrollable, frizzy brunette wig. She adopts a new acting style and hides away the features that made her famous to play animal-obsessed character Lotte Schwartz.

5 | Max von Sydow
The Exorcist
Suggested by njwilson, sunsquashed and typernotfighter
“Max von Sydow in The Exorcist looks very much like Max von Sydow 40+ years later,” notes njwilson. “It’s astonishing makeup work,” continues the reader, referring to the 44-year-old actor’s transformation into 80-year-old priest Father Merrin. Each makeup session would last three to four hours. “I don’t think when I saw it as a kid I realised he wasn’t actually that old,” says sunsquashed. “Super, smashing, great,” adds typernotfighter.

6 | Robin Williams
Mrs Doubtfire
Suggested by Sussexperson and SuperTurboFunkatron
“Robin Williams in Mrs Doubtfire,” proposes Sussexperson. “If anything, an even more credible bit of cross-dressing [than Dustin Hoffman in Tootsie],” adds the reader. The actor had to spend four and a half hours a day in makeup sessions to transform into the Scottish nanny, and the film won an Oscar for best makeup in 1994. His mask was designed in separate pieces to ensure Williams’s facial expressions would appear through the layers of makeup.

7 | Michael Fassbender
Hunger
Suggested by Sussexperson, BeckByrneBrian, DonnaWhite and IllusionOfFairness
Another great metamorphosis that should have made the list, according to our readers, is Fassbender’s performance in Steve McQueen’s Hunger. In the film, “[the actor] played the role of Bobby Sands,” explains DonnaWhite, the member of the Provisional Irish Republican Army who led the 1981 hunger strike in Northern Ireland’s Maze prison. “There are some scenes at the very end where he is so severely emaciated I found it hard to watch,” continues the reader. “Fassbender in Hunger is truly harrowing,” agrees BeckByrneBrian. “He cups his own rib cage!”

8 | Steve Carell
Foxcatcher
Suggested by dressedtodepress, animaux and GiggityG1gg1ty
In Foxcatcher, Carell plays the troubled millionaire John du Pont and he is “practically unrecognisable,” says dressedtodepress. “To be transformative enough to not just see him and think of Anchorman or The Office was impressive,” agrees GiggityG1gg1ty. Makeup sessions lasted three hours every morning for Carell; they included the application of a large prosthetic nose and a drastic skin tone change.

9 | Dustin Hoffman
Little Big Man
Suggested by Pazuzu, Hotspringer and RasDaoud
Many readers noted the absence of Dustin Hoffman’s “largely-forgotten Little Big Man,” as Pazuzu describes the film “in which [the actor] plays the hundred-year-old sole survivor of the battle of Little Big Horn”. Hoffman was 32 at the time and transformed into a 121-year-old man thanks to a set of eyelid prosthetics and add-on foam latex pieces.

10 | Nicole Kidman
The Hours
Suggested by DonnaWhite, dunnock49 and angloserbmom
“I would add Nicole Kidman as Virginia Woolf in The Hours,” says angloserbmom. “She is so completely unrecognisable in terms of looks, accent and body language, it’s difficult to believe that it really is her.” Dunnock49 agrees, adding that “if transformation means being somewhat unrecognisable, I expected Nicole Kidman to be on the list for that wonderful nose in The Hours”. Kidman had to go through a three-hour long makeup session every day to acquire the features of Virginia Woolf.