LEGO: Harry Potter – Diagon Alley Complete Set (75978) BNIB, in Original Packagin. Bought this on release day and never built it or even opened it until today. Comes in original mailer. Brand new and sealed, a couple of wee marks on the corner of thr box,, was always going to happen in transit. Very cool set, and I believe it used to be the biggest Harry Potter set. And getting it tracked.