Plunging ranulas are pseudocysts in which mucous have extravasated either around or through the mylohyoid muscle to escape the confines of sublingual space to involve the submandibular and inferior aspect of parapharyngeal spaces. We describe a rare case of extensive bilateral plunging ranula in which involvement of multiple tissue spaces was well illustrated by magnetic resonance imaging. Clinical and histologic features and pathogenesis have been concisely discussed. The ranulas mostly occur unilaterally and to the best of our knowledge, the development of two discrete ranulas/bilateral presentations in the same patient is especially rare and very few cases have been reported until now. Although the cause of extravasations remains unclear, this case report is significant because of its characteristic possible habit-related etiology.