Two very different men learn about each other in the humorous French film

It all begins with an omelette. Not any old omelette but one made French style with chopped fresh herbs and served en plein air against a backdrop of majestic alpine peaks. As the silent host and his garrulous guest tuck in, it is clear that, at least to begin with, there is one thing this odd couple can agree on.

After giving his unexpected guest a lift to his isolated mountain home, the cook refuses to deviate from his routine. Lunch will be followed by the afternoon siesta. Only then will he look into repairing his guest's sports car that broke down nearby. The mountains are his world, and he is in charge.

The set-up that writer-director Eric Besnard has created here, bringing Pierre (Gregory Gadebois) and Vincent (Lambert Wilson) together, is the perfect scenario in which to send each of his two lead characters up. Recently voted the sexiest entrepreneur in Europe, Vincent, a lithe silver fox, represents everything that tubby Pierre, who left his career and the world behind three years ago, cannot stand. So it's like playboy start-up czar meets passive-aggressive recluse.

They are a perfectly matched pair of opposites. Vincent, protean and living life at a frantic pace, is accustomed to having his image and accomplishments splashed across the media landscape. Whether zipping along aboard his hi-tech catamaran, or raising finance and stitching deals for promising start-ups, Vincent is constantly on the move.

By contrast, Pierre appears to spend his days maintaining his isolated timber home and the garden he has created, wanting no more from the world than to be left alone. He does, however, have some company. Dog, a doggy waif that escaped its owners from Paris, is his constant, if not entirely welcome, companion.

Little by little, Vincent learns that there is more to Pierre than meets the eye. Pierre's skills and accomplishments reveal themselves as Vincent snoops around, making a nuisance of himself. Pierre is refurbishing a bird-watching cabin. There are interesting things going on in what looks like a distillery among bouquets of dried flowers and herbs, and there is a hidden office with an electricity supply that runs a fax, revealing that Pierre has a career. He is a marine biologist, specialising in plankton, with a job offer from San Diego in the offing.

Yet Vincent cannot suppress his derision. Why has he devoted his entire life to plankton? Pierre sets him, and other ignoramuses like me, straight on the importance of plankton ecosystems for life in the oceans.

In another tribute to Pierre's knowledge and skill, we watch him prepare a meticulously detailed meal. He will pack it up and take with him to the home of Camille (Marie Gillain), a native fauna specialist who lives on the lower slopes with her young daughter. It becomes apparent to Vincent that Pierre has fallen in love with her but cannot muster the courage to propose.

It's not as we have expected. Vincent questions his solitary existence too. In a panic attack during an interview that delves too deeply into his personal life, he found he had to face the confronting fact that he was alone, childless, and hedonistic. He reaches for a paper bag to hyperventilate then heads back to Pierre's place in the mountains for another omelette.

Neither its original French title Les choses simples that translates to "the simple things (of life)", nor its English-language title, A Great Friend, quite capture the essence of this film. The irony that a best friend is the one who will tell it to you straight makes an important point, but there are additional things going on here. The film's script is crisp, humourous and thoughtful, serving its characters well, as it also explores what it means to be, and how it is to be a man.

The soundtrack by Christophe Julien, with its Westerner mood accompanying images of men in the great outdoors, infuses a lonesome twang to the film's mood. It's offset by chirpier scenes accompanied by lyrics about a "bright, sunshiny day" from the song I Can See Clearly Now. At the end of the day, the two unlikely friends, Vincent and Pierre, are character types more than rounded-out personalities but there is a lot to like in this jaunty study of their friendship.