immersive — providing or involving deep mental involvement or complete absorption in an activity or experience

a young person wears a large VR headset while holding motion controllers in both hands. Their body moves naturally as they reach and gesture in response to what they see in the virtual world. The person appears completely unaware of the real world around them, lost in their digital experience. Their friend tries to get their attention by waving and calling out, but receives no response. Other arcade visitors stop to watch the absorbed player's animated reactions to their virtual environment. The VR player continues moving and reacting intensely to invisible virtual objects. someone providing deep mental involvement and complete absorption in an activity