Rocked by the storms surrounding his private life and the French economy's tepid growth, French President Francois Hollande has turned to rap. The Élysée Palace has hired part-time hip-hop expert Pierre Evil to pen the president's speeches and help zing up the often dry affairs. Evil, who will be using the more formal Pierre-Yves Bocquet in his day job, is a graduate of the École Nationale d'Administration in Strasbourg , one of France's top schools for civil servants and future presidents, and has been working in the government since the 1990s. Known as "meticulous and methodical" by his colleagues in government, Bocquet has been leading a double life as Pierre Evil, the hip hop music critic. He is also the author of "Gangsta Rap", published in 2005 and the maker of a documentary in 2008, showing interest in the cultural theory behind rap music and its relation to America's black community.

French President François Hollande Dursun Aydemir | Anadolu Agency | Getty Images

(Read more: Hollande avoids personal life as he unveils reforms)

His identity was so secretive that Cyril de Graeve, the editor of "Cronic'art" magazine which commissioned Bocquet, didn't even know his real name. "I remember a discrete man, very neat," Graeve who was his editor in chief for four years at the cultural magazine, told French newspaper Le Monde. "He came across as traditional, small glasses and a simple suit, that is the opposite of the articles he wrote for our pages. I did not know his real name, he worked for us on a voluntary basis, sporadically." Top music critic Boucquet's appointment is a change of pace for the beleaguered Hollande administration: the president's popularity slumped below 20 percent last month for the first time since his election in May 2012, according to a TNS Sofres opinion poll for Le Figaro Magazine. (Read more: France's Hollande says has separated from partner)

Bocquet's dual life was uncovered when it was revealed Bocquet refused to comment on his life as a rap critic, according to French newspaper Le Monde, but looked ahead to his new role. "The only person who writes speeches for François Hollande is François Hollande, my role is just to help him prepare," he said. Industry peers have praised Bocquet's talent as a music critic. French music journalist Fred Hanak told Le Monde that he sees Pierre Evil as one of the top three rap music reviewers in the country. Hanak said that while Bocquet is interested in the American hip hop scene, with artists such as Dr Dre and Snoop Dogg, Hollande's new speech writer is uninterested in French rap. "In my opinion, Pierre Evil is one of the three best French critics of rap," Hanak said, describing Bocquet "as secretive as Batman, Banksy or Kissinger".