Writer:	Joss Whedon
Director:	Joss Whedon
Star:	Anthony Stewart Head (Rupert Giles),  James Marsters (Spike),  Sarah Michelle Gellar (Buffy Anne Summers),  Marc Blucas (Riley Finn),  Nicholas Brendon (Alexander 'Xander' Harris),  Alyson Hannigan (Willow Rosenberg)
Recurring Role:	Kristine Sutherland (Joyce Summers),  Amber Benson (Tara),  Leonard Roberts (Forrest Gates),  George Hertzberg (Adam),  Emma Caulfield (Anya)
Guest Star:	Jennifer S. Albright (Date),  Chet Grissom (Detective),  Alastair Duncan (Collins),  Eliza Dushku (Buffy Summers),  Rick Scarry (Sergeant),  Amy Powell (Reporter),  Kevin Owers (Smith),  Jeff Ricketts (Weatherby),  Rick Stear (Booke),  Craig Patton (E.R. Doctor)

Sarah Michelle Gellar, in an interview with Entertainment Weekly she gave shortly after announcing her decision to leave the show, claimed that this episode is one of her all time favorites because "I thought Eliza [Dushku] was so great." (edit) LOOK HARD: When Faith was in Buffy's body she got on the phone to get a plane ticket. She read out the credit card number and then the EXPIRATION date: 5/01. This could have been foreshadowing what happens to Buffy in May 2001 ("The Gift"). (edit) Faith calls herself "the one and only" slayer even though there are two. (She probably said it because she expected Buffy to be either dead or in jail by that time.) (edit) When Faith in Buffy's body is at Giles's she says "about" in a Boston accent (Faith's accent). (edit) Buffy makes a reference to being able to hear people's thoughts in the episode Earshot and Giles's and Joyce's tryst in "Band Candy." (edit)

Giles: If you are Buffy, then you'll let me tie you up... without killing me... until we find out whether you're telling the truth.
Buffy-in-Faith: Giles, Faith has taken my body, and for all I know she's taken it to Mexico by now. I don't have time for bondage fun. (edit) Willow: We'll get together with Buffy another time. Sometime soon. I think you'll really like her.
Tara: She's not your friend.
Willow: I may have overestimated the "you liking her" factor. (edit) Riley: Door's open.
Faith-in-Buffy: So?
Riley: So my fantasies don't tend to include a bunch of Marines staring in at me. (edit) Buffy: How did you respond so fast?
Riley: I didn't. I was just late for church. (edit) Giles: It's about Faith, not surprisingly.
Faith-in-Buffy: Didn't Joyce tell you? I already kicked that ass.
Xander: I feel a high-five coming on. (edit)

When Faith-in Buffy is at the airport she is wearing a long white and floral skirt and a blue top (interesting choice for Faith, perhaps meant to symbolize her change in attitude as a result of living Buffy's life for a night) but when she gets to the church she has changed from the skirt into what looks like the leather pants she wore the night before. Although it is not that hard to believe that Faith-in-Buffy changed, knowing she would be fighting vampires, it seems strange that the costume designers would go to so much trouble to put her in a skirt for a two-second glimpse of it. (edit) When Giles, Willow, Tara and Buffy-in-Faith arrive at the church and a police officer argues with them, Willow says to him, "But you don't understand" While she is saying this her lips are not moving at all. (edit) When the nurse phoned the watchers council in the previous episode,she only dialled 4 numbers, in reality if she was calling the UK from the US she would need a minimum of 14 numbers. This would be made up of 00 for international dialing, Britain's country code of 44, then a 10 digit British phone number (while British phone numbers have 11 digits, the leading number, which is always zero, is dropped when coming from overseas).

This may not be a mistake as the watchers council may be on some kind of speed dial functionality of that phone. (edit) When they are taking Buffy-in-Faith to the ambulance in the beginning and we look from her point of view at Joyce and Faith-in-Buffy. But Buffy-in-Faith's face is facing upward - meaning her pov would be strictly the stars - there's no way she could see Joyce and Faith-in-Buffy, maybe their heads. (edit) At the end of 'This Year's Girl' when Buffy and Faith fight in Buffy's house, Buffy has straight hair. In 'Who Are You', when the cops come to get Faith, Buffy has wavy hair now. The end of 'This Year's Girl' and the beginning of 'Who Are You' is the same scene. (edit)

Willow: You didn't sense a hyena energy at all, did you? Because hyena possession is just... unpleasant.

This refers to Xander being possessed by hyena in The Pack (1x6). (edit) Faith-in-Buffy: Why, yes, I would be Buffy. May I help you? Buf-fy. You can't do that - it's wrong. You can't do that because it's naughty. Because it's wrong. Because it's wrong. You can't do that. It's wrong, I'll kick your ass. I'm gonna kill you.

This bit of Faith in front of the mirror mimicks Robert deNiro in front of the Mirror in the 1976 film Taxi Driver. His montage- "You talkin' to me? You talkin' to me? You talkin' to me? Then who the hell else are you talkin' to? You talkin' to me? Well, I'm the only one here. Who do the fuck do you think you're talking to? Oh, yeah? Ok. You're dead."

In both cases we see a character trying to adopt a new personality at odds with their previous one and get used to it. And in both cases the speech ends with a line about death- for enemies and for the person whom the character used to be. That this is so for Faith is made clear when she does her two-episode run on Angel following this episode. (edit) Spike: But until then, I'm just as helpless as a kitten up a tree
In reference to the above quote "Is Spike really quoting Frank Sinatra? It seems like too much of a coincidence that this line is almost exactly like the opening line of the song Misty." At the end of Ep # 42 (Lover's Walk) - Where Spike returns after Drew dumps him - we see him drive away from Sunydale listening to a cover of Frank Sinatra's "My Way". While he might not like the original versions of Sinatra's songs, it appears he has a thing for the revanmped versions (edit) Willow: You're Buffy. You and Faith switched bodies, probably through a Draconian Katra spell / Willow: It's a Katra. Or the home-conjured version.
Katra is the Vulcan word for soul or spirit. (edit) Buffy: When I had psychic power, I heard my mom think that you were like a stevedore during sex.
Stevedore is a Spanish derivative word for someone who works at a dock loading and unloading ships. (edit)