With the popularity of virtual reality (VR) devices, advertisers are starting to seek the potential advertising tactics and effects in VR. This study investigates the influence of introducing 3D animated agents on video ad effectiveness in a VR context (i.e., brand/product attitude, brand/product recall, purchase intention, and ad-skipping behavior). Findings from a between-subjects experiment in Study 1 confirmed that when 2D video ads are played in a VR environment, the presence of 3D animated agents will make the audiences enjoy the ad-viewing experience more and promote the audiences’ positive attitudes toward the brand and the product and their purchase intention indirectly. In Study 2, employing a large industry dataset of VR users, we found that the presence of 3D animated agents can also decrease the ad-skipping rate while the 2D ads are playing. This study provides empirical support for the use of animated agents as an effective adversiting tactic in a VR context. How these findings link to previous research and their practical implications are discussed as future directions. • As VR devices become more popular, advertisers are seeking out novel ways to advertise to those users. • A novel approach to VR advertising is to provide animated 3D agents as “buddies” or co-viewers of the experience. • Animated 3D agents indirectly improve ad effectiveness by making the experience more enjoyable. • Analysis of industry data showed that animated 3D agents decrease ad-skipping behaviors. • These data are promising for the further development of advertising in VR formats.