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We present the synthesis and characterization of two series of mononuclear heteroleptic anionic cycloplatinated­(II) complexes featuring terminal cyanide ligand Q+[Pt­(C^N)­(p-MeC6H4)­(CN)]− [C^N = benzoquinolate (bzq), Q+ = K+ 1 and NBu4 + 4; 2-phenylpyridinate (ppy), Q+ = K+ 2 and NBu4 + 5 and 2-(2,4- difluorophenyl)­pyridinate (dfppy), Q+ = K+ 3 and NBu4 + 6] and a series of symmetrical binuclear complexes (NBu4)­[Pt2(C^N)2(p-MeC6H4)2(μ-CN)] (C^N = bzq 7, ppy 8, dfppy 9). Compounds 5, 6, and 7–9 were further determined by single-crystal X-ray diffraction. There are no apparent intermolecular Pt···Pt interactions owing to the presence of bulky NBu4 + counterion. Slow crystallization of K­[Pt­(ppy)­(p-MeC6H4)­(CN)] 2 in acetone/hexane evolves with formation of yellow crystals, which were identified by single-crystal X-ray diffraction methods as the salt complex {[Pt­(ppy)­(p-MeC6H4)­(CN)]2K3(OCMe2)4(μ-OCMe2)2}­[Pt­(ppy)­(p-MeC6H4)­(μ-CN)­Pt­(ppy)­(p-MeC6H4)]·2acetone (10), featuring the binuclear anionic unit 8– neutralized by an hybrid inorganic–organometallic coordination polymer {[Pt­(ppy)­(p-MeC6H4)­(CN)]2K3(OCMe2)4(μ-OCMe2)2}+. The photophysical properties of all compounds were recorded in powder, polystyrene film, and solution states with a quantum yield up to 21% for 9 in the solid state. All complexes displayed bright emission in rigid media, and for the interpretation of their absorption and emission properties, density functional theory (DFT) and time-dependent DFT calculations were applied.