Mark and Arizona are walking along and talking about Callie's dad's imminent arrival. Arizona doesn't know if he's here yet since she's not going to meet him, which to Mark's surprise was Callie's idea. Since she and Arizona just started dating, it's not time yet -- that, and oh, the fact that her dad doesn't know she's now into the ladies might also have something to do with it. Just then, Callie walks in with her dad. An unsuspecting George then runs by but when Callie warns him quickly to run for his life, his confused pause is enough time for Mr. Torres to grab him and throw him up against the wall. Mr. Torres demands to know why he shouldn't kill George right now for committing adultery, so Callie asks who hasn't? She points out that she slept with Mark and that makes her a technical adulterer as well, but unfortunately for Mark that just means Mr. Torres pins him to the wall next. As Mark starts to turn purple, Callie assures her dad that Mark is only a friend, and she's dating someone and is happy -- which causes Arizona to smile to herself. Mr. Torres reluctantly lets Mark go and tells Callie that it's good she's dating, and he'd like to meet the "gentleman suitor." Callie does that TV thing where she stutters too much and overacts as she talks in gender-ambiguous pronouns about how great that person is. Callie then seems to make a decision, which seems a little bit serious but the music stays all wacky as she tells her dad to, "Please be okay with this." She proceeds to walk over and get Arizona, then introduces the other doctor to her dad, explaining that this is who she is dating. With a bright smile, Arizona sticks her hand out and says, "And I really hope you draw the line at throwing women against walls."
Owen has paged Mark to help out with an incoming trauma, much to Derek's disgust and Lexie's agitation. She pops some candy in her mouth as two ambulances pull up -- one has a guy who has been hit by a car and the other has the driver of said car, who immediately charges that the hitee dove in front of him as he was driving. There's yelling back and forth as Malloy, the hitee, gets extremely aggressive and demands that the driver be given a blood alcohol test. As they yell at each other: "Drunk!" "Liar!" Derek and Mark also snipe at each other over who is going to check out the patient first and charge: "You're pathetic." "Ass." Lexie sighs and pops more candy.
Mark and Derek are working on the driver, Gates, who is understandably agitated and upset that he was just driving to the bank when this guy threw himself in front of his car. The doctors don't seem to absorb what he's saying, preferring to snap at each other about who is going to examine him first.