After studying at the Fratellini circus school and the Centre National des Arts du Cirque, Marion Achard formed a troupe with her partner and embarked on a long series of tours. Having always been a writer, her first novel for young people, Je veux un chat et des parents normaux ! was published by Actes Sud in 2012. This marked the beginning of a prolific career as an author, with almost a dozen titles, graphic novels (Tamba l'enfant soldat in 2018, with Yann Dégruel), and appearances on numerous shortlists. Marion Achard, who regularly gives workshops in schools, often depicts the fate of children who are disoriented or confronted with the inertia of the adult world. Her novels, which can be humorous or more serious (Le peuple du chemin, 2017), combine well-crafted writing with breathtaking adventures that are easily accessible to teenagers.

Marion Achard's work features a great variety of situations and settings, although she always writes from the point of view of children. Certain recurring themes, such as roaming and life on the road, are inspired by her own practice as a circus performer (Échange Caravane pourrie contre parents compétents, 2014), or a lack of understanding of the adult world. While their tone is often light, as with the character of Taloula, these novels often deal, in the words of the author, with "bruised childhood, with children who suffer". Some of these novels transport us to distant lands, and several of them have been translated internationally. 

In 2018, Marion Achard decided to examine the contortionist girls of Mongolia, a subject that also touches on her profession as a circus artist. She then obtained a grant from the Institut français Stendhal programme for a residency in Ulan Bator. This opportunity to carry out in-depth research led to Tumee, l'enfant élastique, a novel far removed from Western stereotypes of Mongolia. We follow young Tumee as she performs one of the most difficult positions in this discipline, the Marinelli position, through a story punctuated with flashbacks that tell us how she got there. The story that has found itself on almost a dozen shortlists, including the Pépites d'Or at the Salon du Livre et de la Presse Jeunesse de Montreuil in 2020 and the Pépites internationales, selected by the SLPJ and the Instituts français in 2021.