Lost TV reception last night and missed everything after Peter was being connected September's mind. Can anyone give me a synopsis of the subsequent event?

so toi want spoilers right? otherwise stop lire now.
September tells Peter that he had a son with Fauxlivia. He tells him that he needs to have a child with Olivia. but doesn't explain why. he shows Peter that it was his fault that Walternate didn't see the cure.
He explains that the observers are evolved human beings from the future. they are scientists with the technology to be outside of time and space. they wanted to witness humanities past. hence, why they don't like to interfer.
and he told Peter he had to get back accueil to his Olivia.

Well, he explained the origin of The Observers...and go here to see some gif from the scene link