Related Clues:

• Immersed
• Anything but bored
• Totally attentive
• Not merely paying attention
• Engaged, in a way
• Absorbed in
• Not at all bored
• Undivided, as attention
• Lost in a good book, say
• Engaged, and then some
• Not at all distracted
• All eyes and ears
• Fully engrossed
• Riveted with attention
• Glued to the tube, say