In this article we demonstrate that bright photoluminescence from TCNQ, which hardly luminesces in its solid state, by encapsulating it into crystalline melamine. The photoluminescence quantum yields of TCNQ and the anion radical TCNQ .are typically low due to fast (ps -fs) internal conversion . A better luminescence quantum yield was reported only for some nonpolar solvents , and prolonged fluorescence lifetimes for some micro solvation complexes of TCNQ . Melamine, or 2,4,6-Triamino-1,3,5-triazine, is able to withstand strong ultraviolet radiation, which also might be a likely reason for its abundance in the primordial soup. Melamine-formaldehyde resins are widely used in a variety of plastic products such as kitchenwares as well as coating. Neutral melamine, e.g. melamine in water, is colorless and absorbs ultraviolet light and fluoresces ultraviolet light . It is therefore a perfect host that is transparent in the visible range. Doped melamine single crystals are synthesised by mixing an aqueous solution of melamine and a tetrahydrofuran (THF) solution of TCNQ, followed by crystallisation by vaporization at room temperature. The doping level is tuned by varing the molar ratio of melamine and TCNQ in the aqueous THF. Mass spectrometry combined with UV-Vis spectroscopy elucidates that the dopants are TCNQ and dicyano-p-toluoyl cyanide (DCTC), an oxidation product of TCNQ. Both TCNQ and DCTC -in melamine are found to be fluorescent in the visible wavelength range with lifetimes in the range of 0.7 to 5.0 ns for TCNQ, and 0.5 to 2.5 ns for DCTC -. Exciation-emission wavelength mapping reveals a dominant emission of TCNQ at low doping levels (molar ratios of TCNQ to melamine in the precursor solution below 0.15 %), while at higher doing levels (molar ratios higher than 1 %), both TCNQ and DCTC -comparably luminesce. As pure TCNQ is hardly luminescent in its solid state, these results demonstrate that non-radiative relaxations are much reduced by isolating TCNQ in a crystal of melamine. The colorated melamine single crystals are stable as pure melamine and their luminescence wavelength spans a wide near UV and visible range, which can find various applications in optics and optoelectronics. Our method to encapsulate colourful molecules into crystalline colourless molecules has the potential to make many other non-luminescent organic molecules luminescent. The mixed solution (orange colour as in Fig. ) slowly evaporates, and crystals precipitates and grow over a few days. Crystals were collected and rinsed by THF for further investigation. Panels a-f in Figure are the photographs of the doped melamine crystals prepared with different molar ratios between melamine and TCNQ, (TCNQ, melamime) = (0.04, 100), (0.08, 100), (0.16, 100), (0.31, 100), (0.62, 100) and , where the numbers in the parentheses are the molar concentrations in millimolar (mM) for TCNQ and melamine. The left numbers also correspond to the mole percentages of TCNQ to melamine, namely, 0.04, 0.08, 0.16, 0.31, 0.62 and 1.25 %. It is observed thattThe crystals become coloured as the concentration of TCNQ is increased.