This master's thesis examines the century-long adaptation of Zagreb's Church of St. Blaise as it approaches the 100th anniversary of the architect Viktor Kovačić's passing. Following Kovačić's death on October 21, 1924, the church was almost completely abandoned but is now finished on the inside as well as the outside. Despite having a brief career, Viktor Kovačić is remembered for his important and recognizable body of work and concepts that brought modernism architecture to the Croatian region. The Church of St. Blaise in Zagreb, one of his best-known works of art, was finished in 1915 and continued to function for many years, despite the interior being left unfinished following the final modifications made in the 1930s by architect Stjepan Hribar and his associates, sculptor Ivo Kerdić and painter Ljubo Babić. In the hopes that one of the tender works would provide a suitable solution, an architectural competition was held in 1995 for the conceptual design of the interior of the Church of St. Blaise in Zagreb.The parish priest believed there was an architect who could meet the task, even though none of the works were completed. At the beginning of the millennium, an architect named Željko Kovačić designed a conceptual project. Following nearly ten years of project modifications, the sanctuary's restoration project officially got underway in 2014. Phases II and III of Kovačić's project were finished by 2019, with some interventions and corrections made by the City Institute for the Protection of Cultural and Natural Monuments and the Episcopal Spiritual Table. The 2020 earthquakes hurried the completion of the internal structural strengthening interventions, which were carried out between 2022 and 2023 under the supervision of the architectural firm IVANIIN.KABASHI.ARHITEKT. The entire renovation process was closely monitored by the public and well-covered by the media, subject to criticism and comments from experts and laypeople. After all the interventions, we are left to wonder what the architect Viktor Kovačić would think of the interior of the building that marked his career.