Within perceptual psychology, visual masking describes a process whereby the presentation of one image, the mask, affects the conscious perception of another, the target. Given the right conditions the target can effectively be rendered invisible. There is a dearth of research into the effects of visually masked stimuli within virtual environments, particularly with regard to affect psychology. Of the two studies presented here, the first study was used to establish the efficacy of visual masking using three dimensional, masked objects. Usually, mask and target stimuli are co-planar, with no internal depth disparity. This study found that visual masking is possible within a virtual space using target objects with internal depth disparity. The second study investigated affect driven, choice reactions to three dimensional, masked facial expressions. This study also found an effect, specifically an unconscious bias to navigate away from angry, masked faces and towards smiling, masked expressions. These two studies form a foundation for a wider project: using visual masking within a virtual environment for mood induction, primarily as a cybertherapeutic aid.