He has played everyone from historical figures to comic-book villains, scooping up major acting awards in the process.
Yet 70-year-old Ben Kingsley - who collected the Best Actor Oscar and Golden Globe for the biopic Gandhi (1982) - maintains he is not "a serious actor".
"There's no such thing - it's a contradiction in terms,'' says the Briton, who has also won plaudits for his performances in the Holocaust movie Schindler's List (1983) and the historical fantasy adventure Hugo (2011), among others.
The veteran performer makes this pronouncement to explain his involvement in a rather unlikely project: the stop-motion animated feature The Boxtrolls. He lends his voice to Archibald Snatcher, who convinces a whole town that a gentle race of cave-dwelling, cardboard-box-wearing creatures are out to harm them.
Speaking to Life! and other press in Los Angeles, Kingsley reveals that Laika - the same studio that produced the children's films Coraline (2009) and Paranorman (2012) - had hesitated to send him the script because they thought an actor of his pedigree would turn up his nose at this role.
"They really debated whether or not they should even send it to me because they were convinced I'd say no," says Kingsley, who was knighted by Queen Elizabeth II in 2002. "Which is unfair because of course I'm not a 'serious actor'.
"I just said yes straightaway. It's a beautiful script," he says of the film featuring the voices of Elle Fanning and Simon Pegg.
Kingsley completely transformed his voice to become the sinister Snatcher who tries to exterminate all boxtrolls from the town of Cheesebridge.
And the actor constructed it with the same dedication he gives to creating any character - even going so far as to lie down and contort his face so he could produce a completely different sound.
"Snatcher has this enormous pot belly, and that accentuates, physically, the fact that he is kind of parasitical, hungry, greedy, grabbing, snatching," he tells Life!. "And I wanted the voice to come from that almost echoing emptiness inside of him."
But while the character's working-class London accent was a cinch for Kingsley, who not only mastered the distinctive speech of Indian independence leader Mahatma Gandhi for Richard Attenborough's 1982 film, but also became a vegetarian to get into character - the actor initially found it hard to make it sound like he had Snatcher's huge belly.
"I tried recording standing up and sitting, and then lying down - and there he was. The studio rigged up this amazing seat and footrest and got the microphone there, and then I refused to move."
When he had to pretend to be suffering a horrible allergic reaction to the cheese that Snatcher craves, Kingsley had no qualms about looking silly to do it.
"I just squashed my face so that my mouth was as small as as possible, and squeezed the words out through my mouth," says the actor, gamely demonstrating this.
"I kept saying to myself, 'Don't make any gestures while you're talking, because if you do, you're compensating for something that's not in your voice. It has to come from the voice. So I basically was horizontal and unmoving and let it all come from me to the microphone."
The former Royal Shakespeare Company performer - who spent the first decade or so of his acting career on stages in London and New York - put just as much thought into what sort of British accent Snatcher should have.
"I played with vowel sounds and put the letter 'h' in words where there isn't one. I really wanted to push the envelope of the ambition and neediness in his voice, so he sounds like he's pretending he's from a different class."
The animators took all this and ran with it, he says. Anthony Stacchi, who co-directed the film with Graham Annable, "popped into the recording booth and said, the animators are going to love when you do that".
And although their star recorded his part from a studio in Britain while they were based in Portland, Oregon, the animators sent him a small clip to show him what they were doing.
"In the sequence, he's walking down the stairs and making this horrible, fascist speech, and the animators accompanied this little phrase I used with an extraordinarily flamboyant hand gesture, where Snatcher scrapes back a few strands of hair. And I thought, 'Yup, everything that I'm doing with my voice they're taking and they're using.' So it was very exciting."
The actor saw echoes of the works of William Shakespeare, Charles Dickens and other classic tales in The Boxtrolls, which is loosely adapted from the Here Be Monsters children's book series by Alan Snow.
In Snatcher's desperate social-climbing, he saw shades of the unscrupulous Falstaff in Henry IV part two, while the story of Eggs, the little boy who is raised by the boxtrolls, explores "the plight of the orphan adopted by another tribe", found in Dicken's Oliver Twist or Rudyard Kipling's The Jungle Book. "So there's something eternal in the script, and I love that."
After the award-winning dramatic roles of his earlier career, Kingsley is now embracing more commercial and youth-oriented fare, including playing the villanous Mandarin in the superhero flick Iron Man 3, the second-highest grossing film of last year.
He is also taking on more animation voicework, playing Bagheera the black panther in next year's big-screen adaptation of The Jungle Book.
"It's purely accidental,'' he says of this recent streak of more kid-friendly films, which he credits to film-makers seeing him in a different light after director Martin Scorsese's Hugo.
Kingsley has four children of his own - three sons and a daughter - and is now married to his fourth wife, 39-year-old Brazilian actress Daniela Lavender.
He adds: "I love working with young actors - I find them very inspiring and stimulating because of their purity and directness of approach. So I'm delighted that these doors are opening."
The Boxtrolls is now showing in Singapore.