From the preview:
Come in, agents. Take your seats, don’t stand about. We all have work to do, and the sooner we’re back to it, the better for all of us.
You’ve already had your preliminary briefing on the mission that we’ve codenamed Lumen Fidei. You know the place that you’ll be sent within the timestream—15th century Spain, near the end of the centuries-long Reconquista wars between Christians and Moors. And you know your objective: to join Michel d’Ailly, the Legate of Pope Martin V, and attend a secret meeting of the Christian militant orders. The gathering has been called to discuss a portentous stone, which we suspect has supernatural importance, especially to our enemies. You must find this stone and bring it back to the T.I.M.E Agency before anyone else is able to seize it.