The episode opens with the boys testing out their new killer robot, "MONTE," they built for a robot fighting competition.  After destroying a toaster over, their robot goes beserk and nearly attacks Penny outside the apartment!  With poor Penny in the apartment, Wolowitz does a typical Wolowitz and invites Penny to go to the robot competition in a sleazy way.  However, Penny can't take his rude comments anymore and ends up going off on him in an overly cruel way telling him he's going to die alone.  Wow.  A little too mean Penny.

Wolowitz tehn locks himself in his room at home crying and is unable to help the team with the robot.  As the only engineer in the group, he is completely essential to the project so Leonard calls in his favor that Penny owes him to make her go apologize.  Meanwhile, the boys are challenged by a co-worker, Kripke, who has also built a robot to a little street fight before the competition.  Sheldon quickly accepts and trash talking ensues.  Penny goes to Wolowitz and after he cries his heart out she is very compassionate to him.  When he leans in for a kiss, Penny socks him right in the nose.

Without Wolowitz to help them supe up their robot, the boys lose horribly to Kripke and their robot ends up unfixable.  The episode ends with Penny then insulting Sheldon by calling their robot a toy.  She goes in to apologize.