Anyway, before getting too far ahead of myself, the key developments since last time really revolve around the introduction of new characters - Collins and Wickham.
Firstly Collins - it turns out that as a result of a rather arcane arrangement in Mr Bennet's will, his estate must be passed to a male heir, and so cannot go to any of his five daughters. Mr Collins, his nephew, now a clergyman under the patronage of a Lady Catherine de Bourgh (who we later discover by coincidence is Darcy's aunt) lives some distance away, and is not well thought of by Mrs Bennet due to what she considers to be his unfair claim on her husband's estate. Collins comes to visit, and turns out to be a bit of a wally. However, he has what he considers to be a cunning plan, namely to marry one of the daughters and thereby keep the estate more closely 'in the family'. Mrs Bennet thinks this a splendid idea and is won round. (On the whole we tend not to hear much about what Mr Bennet thinks.) Collins makes a fool of himself at the Netherfield dance, and then makes even more of a fool of himself when asking for Elizabeth's hand in marriage, thinking that she is being charming and coy, when she is flatly refusing his proposal.
And secondly Wickham - the younger Bennet sisters, Kitty and Lydia, are keen on a man in uniform, and like to go to town and chat up the soldiers who are based there. On one occasion they take Elizabeth along and she meets Wickham, recently arrived to join up. They spend the evening deep in conversation at her aunt and uncle's house, where it transpires that Wickham and Darcy have a long and complicated past. Apparently Wickham's Dad worked for Darcy's Dad, and Wickham and Darcy grew up together, almost like brothers. There was an understanding that Wickham was to be looked after by Darcy's father's will, but something went wrong, and now there is significant ill-feeling between the two, and we are left with the clear impression that it is all Darcy's fault. Anyone who is anyone is at the Netherfield ball, but Wickham is conspicuous by his absence, conveniently having business to attend to elsewhere. Darcy and Elizabeth dance together, but it is frosty.