Lies, accounts and performance aimed at deceiving the audience, always haunt the researcher’s mind. Whether one chooses quantitative or qualitative (even ethnographic) means, researchers come up with methodological devices (triangulation, re-interviewing, being there, rapport) as ways to eliminate distortion from researchers and respondents, and to get true statements and categories from our social subjects. In this paper I take advantage of an “identity lie” (or a fake identity) which came up while I was working with Malvinas war veterans in Buenos Aires (1992). By comparing veterans’ identities to my own identity as an anthropologist in the field, I show that lies are part of metacommunicative competences by which both vets and I learn to talk and act about “Malvinas”. By means of this reflexive twist, deceptive informants appear to challenge our methodological assumptions, not just because they alter the reliability of our accounts, but rather because they illuminate the very core of our identities at work.