Carrie wonders why she has never become friend with an ex-boyfriend, and decides that if she must start with someone, that someone mind as well be Mr. Big. She calls him up for inviting him over for a dinner, where he breaks the news that he's proposed to his new girlfriend, Natasha. Shocked, Carrie storms out of the restaurant, shouting and yelling about how with her he had a commitment problem for 2 years, but had found no difficulties on proposing to whats-her-name after 5 months. Meanwhile, the other gals try to find friends themselves. After running away (literally) from Steve, Miranda receives a visit from him in her place and ends up in bed with him - they're friends who have sex. Charlotte tries to become friends with a horse and overcome her trauma caused by her best friend - a horse - who threw her from his back when she was a child. And Samantha faces a challenge: she meets a man with a huge penis. So big that she isn't sure she can make it. When the doubt becomes a certain,