When I last saw him on the screen, in 1990 in Green Card, he was normal-sized and positively fanciable. Since then his love of food and his habitual intake of five bottles of wine a day has taken its toll. (Remember when he was refused access to the lavatory on an aircraft bound for Dublin and used the floor instead? "I'm not a monster, I'm just a man who wants to pee," he memorably explained.)
So he hasn't aged well (he's 64), though perhaps not as badly as Brigitte Bardot, who used to be unutterably gorgeous and sexy but in old age, 78, is bloated, ugly and cross. Her ultra-right politics are racist and her admirable devotion to animals seems to have morphed into lunacy.
But unlike Bardot, Depardieu kept on acting, maintained his popularity and was forgiven all kinds of bad behaviour.
Anyway, both of these erstwhile sex symbols have given their country an uncomfortable few weeks but deserve our thanks for adding greatly to international gaiety.
It all began with the election in May of Francois Hollande, who was supposed to restore to the presidency the dignity Nicolas Sarkozy – with his bling, his celebrity marriage to Carla Bruni and his administration's financial scandals – was alleged to have robbed from it. Hollande has since had a torrid time with an ongoing, very public war between his ex and present partners that has made the public decide he's weak.
His announcement of a 75 per cent tax on income over €1m was supposed to bolster his socialist and economic credentials, but has led to a stream of rich people taking umbrage and seeking sunnier fiscal climes.
In a blaze of publicity, Depardieu, a successful businessman as well as bon viveur who had supported Sarkozy, bought a house across the border in Belgium, a decision described as "shabby" by Prime Minister Jean-Marc Ayraul. The left-wing newspaper, Liberation, called him a "drunken, obese petit-bourgeois reactionary".
Depardieu's response was to write a public letter to all his critics. "I'm leaving because you believe that success, creativity, in fact, differences should be punished," he wrote.
"I won't cast a stone at [people] who have cholesterol, hypertension, diabetes or too much alcohol or those who fall asleep on their scooter: I am one of them, as you dear media outlets like so much to repeat." He announced he would relinquish his French passport and at a pre- Christmas farewell party, jokingly added: "Putin has already sent me a passport." [Russia has a flat tax of 13 per cent].
Rather late in the crisis, on New Year's Day, Hollande phoned Depardieu to ask if he was serious, and was accused of "spitting on success".
Putin, who is nothing if not an opportunist, had already announced that if a passport was what "Gerard" wanted, he should consider it done, and citing Depardieu's services to cinema, broke all the rules and pressed the document into his hands last Sunday at a much photographed huggy meeting at his pad in Sochi, on the Black Sea. Depardieu declared that he adored Russian culture and that his father had been a communist. He also rather confusingly explained that he remained French and would have dual Belgian nationality.
Not to be outdone, Bardot, who had denounced the persecution of Depardieu, announced that she would take up Russian nationality if two tubercular elephants at Lyon Zoo were put down. She was attacked by another minister as "hysterical".
Corinne Lepage, a high-profile MEP, has gone public with a demand that other countries and, indeed, her fellow-countrymen stop treating France as a planetary "laughing stock". How could a country "blessed by the gods with its culture, food and landscapes, that is the world's most popular tourist destination and seen by many as an Eldorado, come in the space of a few weeks to be treated like a bogeyman?" she enquired. She had no problem with Depardieu moving to Russia and making "a man-sandwich" with Putin, she added.
Meanwhile, Depardieu failed to turn up at a Paris court last Tuesday to face the drunk-driving charges he acquired when he fell off his scooter.
His lawyer explained he wasn't dodging justice, but had to give priority to a meeting abroad with movie producers who want him to play Dominique Strauss Kahn.
Now I vividly remember deeply sympathising with the New York maid who alleged Strauss Kahn had burst naked out of his hotel bathroom and assaulted her. (He's since settled the civil case she took against him.) But being attacked by someone the size of Depardieu could prove fatal.
Could the answer be to have the dispensable Bardot play the maid and Putin volunteer to be the second man in the sandwich?