The Hall of Elders’ Crossing is the alignment of the planets. James thinks this is a place but it actually is an event; the alignment of the planets which he first hears of from Ted and Petra. Madame Delacroix has the Divination class and Constellation Club plotting out star charts, working out timing and mapping out this astrological event. Merlin’s return is to occur during this time if all his relics are gathered in the proper place. Zane declares he knows when the event will occur because he is mapping out star charts for Madame Delecroix in the Constellation Club, but Prof. Snape informs the trio that they are only determining the hour, Madame Delacroix has known the date for over a year and it is a day earlier than she is leading them to believe.