The French actor Daniel Auteuil isn’t prone to naked displays of anything. The 57-year-old is no sex symbol, even if he did have an 11-year romance with the walking goddess Emmanuelle Béart, his co-star in Claude Berri’s “Manon of the Spring,” the film that put him on the map in 1986. Twenty years later, Mr. Auteuil’s understated acting is one of the best things in modern French cinema.

Mr. Auteuil, who can be seen in three films playing in New York at the moment, is probably best known for 2005’s “Caché,” Michael Haneke’s haunting exploration of postcolonial guilt. He was spellbinding in that film as a successful Parisian TV host unraveled by a series of menacing packages, his sharp-edged performance cutting right to the fear and denial that underlies bourgeois self-satisfaction. The scene near the end in which he draws the curtains and curls up in bed is an unsettling anti-climax: no truth and reconciliation, just agonizing uncertainty, and the image of an embattled man unsure how to surrender without the aid of a sleeping pill.

Mr. Auteuil has pinched, asymmetrical features; his face looks like Robert De Niro’s jammed in a pressure cooker. Like Mr. De Niro, he has taken on roles lately that expose the weaker side of men who are used to getting their way. That side can be awfully funny, as in Francis Veber’s “The Valet,” currently in theaters, in which Mr. Auteuil plays a CEO having an extramarital affair with a supermodel (Alice Taglioni). When their liaison is exposed in the tabloids, he sets out to convince the press and his wife (Kristin Scott Thomas) that the face of Chanel is actually involved with an unassuming young man (Gad Elmaleh) who parks cars for a living.

“The Valet” is the kind of jazzy, old-fashioned farce only Mr. Veber seems to make anymore. The director’s 2001 film “The Closet” also starred Mr. Auteuil, but as the comically misunderstood straight man. In “The Valet” that role goes to Mr. Elmaleh, who is a bit too cool and unflappable for an Everyman but serves as an excellent foil to Mr. Auteuil’s high-strung executive.

When the bigwig’s mistress unexpectedly warms up to the valet, with whom he’s obliged her to shack up, his carefully planned charade starts to take on a life of its own. He gets a bit twitchy, and when the couple has curtains installed, he blows his top. What he doesn’t know is that his vengeful wife, not fooled for a second, had the curtains put in. Mr. Auteuil’s villain acts like the man in control — he’s a CEO, after all — but is in fact the butt of the joke. There’s no bully or patrician in Mr. Auteuil’s tightly wound millionaire; at heart he is a regular guy, a petit bourgeois in an extra-fine suit.

Conversely, the great achievement of Paolo Virzí’s “Napoleon and Me,” at the Tribeca Film Festival, is its refusal to cut one of history’s most famous Type-A personalities down to size.

Mr. Auteuil, in the title role, opens a window on the inner life of a grand historical figure but never fully lets his guard down, thus preserving the essential mystery of what fueled Napolean’s titanic ambition.

Exiled to the Italian island of Elba, he first appears as the iconic Little Corporal, head squished turtle-like between his bicorn and high-collared trench coat. From a distance he is an almost comedic figure, which is what makes Mr. Auteuil’s complex, serious portrayal so startling. His Napoleon has a self-deprecating side, but no one dares laugh at him, and he generally lacks the patience to be charming. (He resorts to a joke during an awkward moment with Tuscan hosts, but delivers it as if passing a kidney stone.)

Napoleon’s irrepressible ambition masks hidden anguish, and he secretly yearns to have his childhood back. But the film does not make him too psychologically accessible; Mr. Auteuil’s world-weary general paces briskly through life and retains the stature of the Napoleon found in history books. Key here is Mr. Auteuil’s acute nervous energy — he shoots darts with his eyes, and his short beak of a nose has never looked more emphatic. The world conqueror is both man and superman, in his time and outside it; his new neighbors on the little island of Elba may think they know him, but he eludes them all in the end.

Francois, the antiques dealer at the center of “My Best Friend,” also playing at Tribeca, is a more recognizable breed, a tense modern Parisian not unlike the one Mr. Auteuil played in “Caché.” He has achieved success at the expense of meaningful relationships, though he doesn’t fully realize it until his business partner (Julie Gayet) challenges him to find someone who doesn’t think he’s a jerk.

Dismayed to find he can’t, Francois enlists a genial taxi driver to help him make friends. The main payoff, though, is the companionship — ultimately, a precarious one — the two of them gain.

Ebenezer Scrooge comes to mind, but Mr. Auteuil’s Francois is no one’s idea of a misanthrope. The director, Patrice Leconte, cast Mr. Auteuil with this contradiction in mind. “He seems so open, affable, and benevolent, that I found it novel to see him play a guy who has no friends,” the director explains in the film’s press notes. But Francois views people as objects; he has never made an effort to get to know his associates and colleagues, but selfishly expects them to like him. When he learns they don’t, he explodes in a poignant burst of embarrassment and disbelief.

But then Francois moves forward — he is a results-driven man, after all. He thoroughly abases himself in several desperate attempts to meet strangers, but Mr. Auteuil’s nuanced, painfully funny performance underlines the fact that people don’t transform overnight.

Nor, Mr. Auteuil reminds us, do they have their emotional trajectories scrawled all over them. Few people are more aware of this than Mr. Leconte, who has made three films with him. “The subtlety and extreme economy of his acting impressed me,” the director said. “To express so much by doing so little, that’s the very definition of grace.”