This is one of my favorite Garcia Flynn moments so far. He realizes Lucy and Rufus have outsmarted him, and his reaction is amusement, not frustration or anger. Dare I say there’s even some respect for Lucy, Rufus, and their combined intellect mixed in there? (I do dare.)
Kudos to Goran Visnjic for letting the audience see Garcia thinking in this scene; it’s clear in the way his eyes track and his head and body turn.