Best Top Gear Episode for a New Viewer?

Got into a conversation with the girlfriend the other day about our favorite TV shows and naturally, Top Gear came up for me. I told her something to the effect of "Don't worry, I don't expect you to watch it with me. It's just a car show." However, her being the awesome girl she is, told me that if I liked it so much, she'd like to try it.

So now I'm at a loss of what to show her. She's a big Friends fan so we agreed we'd watch the Matt LeBlanc episode and one of my choosing to see if she'd like it. I wanna show her an episode that really gets at the heart of what Top Gear is. I want an episode that shows Jeremy, Richard, and James' characters, how different they are, and how entertaining they are together. Ideally it'd be a challenge episode, but two-part specials are also a nice loophole to the two episode agreement.

I've seen practically every episode of Top Gear, but trying to remember the best one is like trying to remember my favorite commute to work. So I turn to you Oppo, what's the best episode to introduce a new, non-gearhead viewer to Top Gear?