"Buenas tardes!" Why did Vladimir Putin greet two Russian children who had just stepped off a plane in Spanish on August 1, during the biggest prisoner exchange since the collapse of the USSR? That's because, according to the Russian authorities, they didn't speak a word of Russian, and had only known their true nationality for three hours. Until then, they had been living in Slovenia and thought they were Argentinians. Their parents, Artem Dultsev and Anna Dultseva, were secret agents in Russia's "illegals" program. They had been living under complete cover for at least 12 years under false identities: "Ludwig Gisch" and "Maria Rosa Mayer Munos".

In this video, Le Monde tells the story of this spy couple, starting with the acquisition of their false identities and the start of their fake life in Argentina, before they departed for Slovenia, where they were eventually unmasked. We also explain Russia's strategy with these spies.

Read more about Putin's "illegal" spies in the article below.