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Advanced intermetallic TiAl alloys are typically used in high-end aerospace and automotive applications. This class of materials outperforms Ni-based superalloys in weight reduction, high temperature strength, corrosion resistance, and creep properties of up to 800 °C. However, TiAl alloys suffer from a distinct lack of ductility and elongation prior to fracture at room temperature. Therefore, the fracture properties of a TNM+ alloy were determined in micro- and nano-scale notched cantilever bending experiments. These in situ experiments were performed in a transmission electron microscope to track crack propagation during fracture along selected interface types or phases. Consequently, crack propagation and global ligament stress were determined, and strain maps were recorded using a nano-beam diffraction mapping technique to assess the strains prevailing in the initial microstructure and dislocation densities. The experimental results were complemented by mechanism-resolving molecular dynamics simulations, which allowed us to identify the crack tip processes. Thereby, the here presented scale-bridging approach evaluating the fracture properties of a tailored TiAl alloy, allows us to identify the mechanisms of crack propagation and demonstrates the benefit of combining micromechanical experiments and atomistic simulations.