Martha Jones is introduced to Eve as a doctor. Eve says charmed and gives her a habitual glanceover. She's already catalogued the entrances and exits of the room, the clearest path, the structures she can hide behind -- how to fire a shot, gain cover behind the couch, and exit the door. It's habit, really.
Seeing Martha is unarmed, Eve meets her eyes with a ready smile. Martha's eyes are not full of good humor like the rest of the party, not even the spark of recognition of attraction. No, there's something hard in those eyes, and Eve knows she's been caught.
"A doctor, really?"
"Yes," Martha replies.
Liar, she thinks, because Martha is no more a doctor than Eve is a secretary.