This article documents the importance of collaborative dialogue as part of the process of second language learning. The stimulus for the dialogue we discuss in this article was a reformulation of a story written collaboratively in French by Nina and Dara, two adolescent French immersion students. A sociocultural theoretical perspective informs the discussion of three sustained examples of the learners' "talking it through" as they confront and resolve many language-related problems while comparing their story with its reformulation. A pre-test/post-test design allows us to demonstrate the combined effects on second language learning of the reformulation and the students' reactions to it.