This paper proposes to analyse the shift from one media to another, here from books to TV series, when talking about a specific genre, here the detective story in literature and in the TV show Broadchurch. It is a TV show that deals with the investigation lead by DI Alec Hardy and DS Ellie Miller on two different murders of children, one in each season. In this research paper, I argue that the 19th century first detective stories in British literature imposed a common base for everything detective related, even today in the 21st century, but that there needs to be a part of emancipation linked with social evolution. I chose this research problem because I wanted to study the detective genre in literature that I never really studied before, neither in high school nor in university, and I thought that it would be an interesting point of view to link it with a modern medium such as a TV show. In the present work, I use an intermedial approach. I shall compare the different literary detectives and then, I will go back and forth between literature and the TV series. The idea of an intermedial approach is interesting because there are more and more works done about TV shows, but not many of them are about Broadchurch. As for the bibliography, my studies are based on three main detectives: Sherlock Holmes, created by Conan Doyle, G. K. Chesterton's Father Brown, and Agatha Christie's famous detective, Hercule Poirot. My primary sources are mainly some of the novels or short stories in which they appear, for instance each of their first appearance, and the TV series. As for the secondary sources, I base my reflection on studies about detective stories written by Deleuse, Mellier or Duflo for instance, and also on studies about TV series, by Esquenazi and Jost.In the course of this analysis, I will try to answer the following question: how did the archetypical detective in British literature inspired the character of Alec Hardy and the TV series Broadchurch? In order to answer this research problem, I decided to divide my analysis into three distinct chapters. The first chapter deals with the comparison between the literary detective and the detective of the show. The second chapter will be about the idea of adaptation, and the evolution of the detective genre. My last chapter will be about the construction of the story in Broadchurch, and will show how it is a detective show that differs from others.Up to this point in my research, I had some difficulties. I discover that even though I selected three fictional detectives, it is hard to have a complete overview of the works in which they appear because of the numerous stories they are involved in. Another difficulty is to have a methodological approach to watch a TV show. It was indeed challenging to have a critical point of view on a TV show and to find which are the points of interest in each episode. As for the weaknesses of my paper, I am aware that the TV show Broadchurch is not that notorious. It only gathered between 6 and 8 millions viewers in the United Kingdom, and this number decreased between the first and second season. For further studies, it would be interesting to use this research paper and apply this approach to another show, as Broadchurch inspired a lot of different shows, such as Gracepoint in America or Malaterra in France. This approach could also be used for another genre. It could impact people to make them ask themselves if there is such a link between one media and another one while watching a TV show for instance.Finally, if I were to start again, I would make sure to read more books before the beginning of my studies, to have a more expanded knowledge especially about the three literary detectives I am dealing with in this research.; Comment naissent les détectives que l’on voit aujourd’hui sur nos écrans de télévision ? Sont-ils simplement issus de l’imagination des réalisateurs et des scénaristes de séries télévisées ? Ou bien vont-ils prendre racine dans un passé plus ou moins proche, s’inspirant d’un patrimoine déjà existant ? Voici la question que je me suis posé à la rédaction de ce mémoire. En prenant l’exemple de la série Broadchurch, j’ai voulu essayer d’expliquer d’où vient l’inspiration pour la création du détective et de l’intrigue.J’explique dans un premier temps, quelle est l’image du détective dans la culture britannique. En partant de trois détectives de la littérature anglophone très connus (Hercule Poirot, Sherlock Holmes et Father Brown), je dessine le portrait du détective « type » que l’on trouvait en littérature au XXe siècle. Puis, je compare cet archétype du détective à Alec Hardy, détective télévisuel de la série télévisée Broadchurch, elle aussi, série britannique.Dans une seconde partie, j’explique comment les choses ont évolué dans la construction de l’intrigue du roman policier à la série policière. Quels sont les éléments clés d’un roman policier ? D’une série ? Ces points clés se ressemblent-ils ? Et surtout, comment ces fondamentaux du genre a pu évoluer entre la littérature et la télévision, mais aussi entre le XXe et le XXIe siècle.Enfin, dans une dernière partie, je me concentre principalement sur la singularité de Broadchurch, ou pourquoi avoir choisi cette série pour cette étude plutôt qu’une autre. En effet, bien loin des classiques des séries policières, la série de Chris Chibnall parvient à s’illustrer d’une manière bien à elle, qui sur certains points rappellent les détectives littéraires du XXe siècle, et qui sur d’autres, prouvent que c’est une série bien ancrée dans son temps.