I thought I was looking at Cassiopeia with its 'W' shape, then I released that it was a series of lights moving silently across the sky in a straight line, but in a zig zag formation. There was a much brighter light, then two, that appeared to be flying up and down alongside the formation, almost as if they were escorting them. After a couple of minutes they suddenly disappeared, then about five minutes or so later, they suddenly re-appeared back in the spot where I initially saw them, taking the same path I'd watched them take a few minutes earlier. Same bright light, then two, and then they all disappeared exactly the same as the first time. It was as if somebody was replaying it again.