The use of inexpensive K₂S₂O₈ in water at room temperature for synthesis of bis(indolyl)methanes (BIMs) from simple indoles and alcohols is reported. The key step involves the conversion of alcohols to their corresponding carbonyl compounds and subsequent condensation with indoles from in situ generated radicals. Also, the challenging aliphatic alcohols showed good performance in the synthesis of BIMs. We also carried out a detailed exploration of the mechanism.