Oh, whenever there's a stellar alignment, there's always trouble!
This scenario - which serves as an excellent campaign starter or equally-well as a one-off - is no exception. It begins with the Personas (player-characters) moving in the highest intellectual circles in Arkham, with a concert to attend and a charity poker tournament to participate in, not to mention academics and local leaders to hob-nob with... while those characters new to Arkham can explore.
Then those pesky stars line up!
This gives an opportunity for some spectacular exploration, through a portal to a beautiful yet dead city on some far distant planet, no less.
Naturally, it is not all plain sailing and when the characters return to the reality of Arkham, they soon realise that all is not right and they will have to take a lead in putting matters to right. With atmospheric descriptions, plenty of people to talk to and occurrences to investigate, the characters will be sucked straight in and find that they have a pivotal role to play.
If used as a campaign starter, they will find that they have established themselves as usful and potent players on the Arkham scene. If it's a one-off, they'll hopefully leave with some satisfaction of a job well done.
Should you be looking to capture the essence of the Dark Aeons game, this will provide a good introduction to the richness and strangeness of this alternate reality.