Pokemon Heart Gold Help pl0x

So I beat the blackthorn Gym and I already did the whole Dragons Den ordeal. I went back to the first town and am trying to surf east towards the E4 but I am stopped by the girl charecter. Can anyone help me out here?

Get the Master Ball from Elm, then head to Ecruteak City and do the event with the Geishas. Chances are that you'll need to get Ho-oh from the top of Tin Tower.