Just today, Fantasy Flight Games have announced the latest expansion for the Arkham Horror board game is now available.
In an official press release, the studio gave details about the new Secrets of the Order expansion. It states, "the unquiet spirits of the dead cry out and ghouls stalk the midnight streets of Arkham. Derelict portals yawn open between our existence and the horrific unknown, and even in the storied French Hill neighborhood, the Order of the Silver Twilight plots their path to greater power."
As the description implies, Secrets of the Order's expansion will focus on the neighborhood of French Hill set in the iconic town of Arkham from H.P. Lovecraft's Cthulhu mythos, and it will feature on an evil cult and horrific portals that pull their victims into an unspeakable underworld. Secrets of the Order will also feature two several double-sided map boards, giving a new refreshing spin on the otherwise familiar locations, adding some unexpected novelty and spacial management to the investigation. The expansion will include four new investigators like the soldier Mark Harrigan and the plucky pilot Winifred Habbamock, three brand new narrative scenarios, over 130 event and encounter cards, brand new monsters and conditions to navigate, and a brand new map tile.
Bear in mind that Secrets of the Order is not a standalone expansion. If you want to play this, you will need Arkham Horror Core Set Third Edition first.

As mentioned above, Secrets of the Order is available right now. You can order it right now from Fantasy Flight Games own website or place an order at your local game store. It is currently being sold for $39.95.
Overall, the idea of portals and managing different sides of a map sounds like a great way to mix up the formula of Arkham Horror. If you want to add more interdimensional insanity to your games, your time has come.