Party hard ziam

Harry styles was Liam payne's best friend also along with Niall Horan.
Harry's boyfriend was Louis,Lou Tomlinson.
Lou's best friend Is Zayn Malik.
Zayn Malik is the hottest guy ever,he's popular,a trouble maker but Niall and Liam haven't met Zayn.
All the boys live in London but Zayn and Louis.
Everyone knows Zayn because he went to the High school in London,Liam was in Wolverhampton and Niall was in Ireland during that time.
Zayn and Liam meet in Harry's birthday party.
What will happen?