“What You Don’t Know” is an aggressive, high-energy 1989 dance-pop and new jack swing track that served as the explosive title single for Exposé’s hit sophomore album. The song features a hard-hitting, fast-paced production driven by sharp, industrial-style drum machine beats, punchy horn-section samples, and a heavy, grooving synth bassline. The track leans into a tougher, more urban contemporary sound than their previous records, showcasing the group’s evolution alongside the changing trends of late-80s pop.

The lyrics serve as a fierce, sassy, and empowering warning to a deceitful, unfaithful partner, letting them know that their hidden secrets and lies are finally being brought to light. Featuring Gioia Bruno delivering the lead vocals with an intense, powerful rock-style rasp and immense attitude, the song radiates a sense of betrayal turned into fiery strength. Supported by a highly stylized music video and the group’s powerhouse backing vocals, the track became another massive multi-platinum hit that ruled dance floors worldwide.