["Psychology &Marketing, EarlyView. ", "\nABSTRACT\nBrands are more frequently adopting virtual influencers (VIs) to lead activism campaigns. However, little is known about when and how such activism effectively drives consumer engagement. This research, in Study 1, examines 14,464 Instagram posts from 18 diverse VIs using large‐scale analytics to assess engagement intensity and the dynamics of this VI‐driven brand activism. We find that VI‐driven brand activism not only increases engagement volume but also paradoxically stimulates meaningful conversational participation through comments, alongside passive expressions of approval through likes. This pattern signals a shift from surface‐level affective responses to heightened conversational engagement, reflecting greater cognitive and behavioral investment by consumers. Study 2 shows that brand activism driven by VIs increases the intention to engage, compared with that driven by human influencers. Crucially, more realistic VIs are associated with greater engagement intensity, suggesting that humanlike characteristics enhance consumers' willingness to interact with VI‐generated content. Next, the type of ownership also matters: non‐brand‐owned VIs outperform brand‐owned ones in engagement intensity. Credibility benefits hinge on nonbrand ownership, as it heightens the perceived legitimacy of the VIs and, in turn, increases the intensity of consumer engagement. However, the engagement benefits of nonbrand ownership are more pronounced for active engagement (comments) than for passive engagement (likes). These findings provide actionable insights for selecting VI‐based brand ambassadors to promote activism campaigns."]