that we were failed on every level. as well as the police, there's been damning criticism of the private companies responsible for security at the arena. the venue was operated by a company called smg. it contracted its security for events to showsec. both admit some failings. both say they have learned lessons. central to it all is what happened in the city room prior to the explosion. an hour before the concert ended, while the audience was still inside the arena, here is abedi, walking in. he goes straight to the stairs and up to a hiding place he checked out before, out of sight, on this balcony, in a cctv blindspot.