A non-isolated pentagon rule metallic carbide clusterfullerene containing a heptagonal ring, Sc2C2@C-s(hept)-C-88, was isolated from the raw soot obtained by electric arc vaporization of graphite rods packed with Sc2O3 and graphite powder under a helium atmosphere. The Sc2C2@C-s(hept)-C-88 was purified by multistage high-performance liquid chromatography (HPLC), cocrystallized with Ni(octaethylporphyrin), and characterized by single-crystal X-ray diffraction. The diffraction data revealed a zigzag Sc2C2 unit inside an unprecedented C-s(hept)-C-88 carbon cage containing 13 pentagons, 32 hexagons, and 1 heptagon. Calculations suggest that the observed nonclassical fullerene could be a kinetically trapped species derived from the recently reported Sc2C2@C-2v(9)-C-86 via a direct C-2 insertion.