Pedagogical agents are theorized to increase humans’ effort to understand computerized instructions. Despite the pedagogical promises of VR, the usefulness of pedagogical agents in VR remains uncertain. Based on this gap, and inspired by global efforts to advance remote learning during the COVID-19 pandemic, we conducted an educational VR study in-the-wild (N = 161). With a 2 × 2 + 1 between subjects design, we manipulated the appearance and behavior of a virtual museum guide in an exhibition about viruses. Factual and conceptual learning outcomes as well as subjective learning experience measures were collected. In general, participants reported high enjoyment and had significant knowledge acquisition. We found that the agent’s appearance and behavior impacted factual knowledge gain. We also report an interaction effect between behavioral and visual realism for conceptual knowledge gain. Our findings nuance classical multimedia learning theories and provide directions for employing agents in immersive learning environments.