Fluorogenic reactions have recently emerged as a powerful tool for detection, diagnostics, and biosensing applications in a chemical and biological context. However, conventional fluorogenic systems reported to date rely on energy- or photoinduced electron transfer within the probes. Our communication demonstrates a conceptually new approach for generating a strong fluorescence signal through chemical bond formation mediated by a heavy-atom removal process. This method has favorable photophysical properties such as exceptional quantum yield and very low limits of fluorogenic DNA detection.