In the story of the Penitents (ar. Tawwabun) we are told about a group of men from Kufa in the 7:th century, who deeply regret that they did not support Husayn b. ‘Ali, the grandson of the Prophet, when he was assaulted and killed at Karbala in 680 CE. In their remorse, they first discuss the option of committing collective suicide. As this is prohibited in the Qur’an, however, they decide to seek revenge by going against the Umayyad army. This will certainly lead to their death, and they accept this as martyrdom for true Islam which will cleanse them from their sin. As the story most likely is written down as early as the middle of the 8:th century, and probably has earlier roots, it is remarkable that very little attention has been paid to it in academic research. In spite of its old age, it incorporates many elements that later came to be basic in Shi‘ite Islam. At the same time, however, other components in later Shi‘ite theology and ritualthat began to develop around the mid-8:th century, such as the Shi‘ite imamology, are lacking in the story. Thus, it is an important link to the understanding of the development of early Shi‘ism. In this paper I will introduce a research project concerning the story of the Penitents that is financed from the Swedish Research Council. In the project, the story will be studied from three perspectives. First, the history of tradition will be focused, and three different versions of the story, i.e. the versions by Ibn A‘tham al-Kufi, al-Baladhuri and al-Tabari, will be compared and the relations between them will be analyzed. Second, special attention will be paid to the theological ideas expressed in the text in relation to those that developed later in Shi‘ism. Third, the rituals performed in the story will be studied in connection with rituals in the surrounding culture as well as in later Shi´ism.