Mike has been acting weird lately - making excuses, being evasive, smiling to himself when he thinks no one is looking. And the hickeys are the nail in the coffin. Will knows Mike has a new girlfriend that he hasn't told anyone about, and he's determined to dig up clues about this secret lady-love. Not because he's jealous. Will has moved on from Mike - really. He refuses to spend his whole life pining over someone who's never going to want him. He just wants to find out about this mystery girl, to make sure she's right for Mike and she's treating him well. But when Mike invites his lab partner from biology along to a party, Will is a tad distracted from his mission. Because Emmett is pretty clearly gay. (Spoiler alert: Mike isn't dating a girl.)