The present paper reports the results of an experiment designed to examine the effect of a celebrity commercial on viewers’ subsequent dishonest behavior, hypothesizing that viewing a celebrity seemingly lying for money stimulates viewers to also lie for money if the opportunity arises. A group of students watched a short commercial endorsed by a popular Israeli actress (experimental treatment) whereas two groups of students watched either an extract of the same length from a dramatic film starring this actress or a commercial of the same length endorsed by an anonymous actress (control treatments). Subjects who watched a commercial were also asked if, in their best impression, the actress was also willing to endorse any product for a suitable amount of money. All subjects were than offered to perform a money-rewarding simple task which involved an opportunity to increase their payoff by cheating with no possible detection. The results reveal that subjects who watched the popular actress' commercial cheated significantly more than subjects who watched either her dramatic film extract or the anonymous actress’ commercial and that cheating increased with viewers’ impression that the popular actress was also willing to endorse any other product for money. A modified version of the self-concept maintenance theory, supported by a formal model of rational-choice cheating, explains our results.