Work on the mine was slow, and not without difficulty. Despite taking on new conspirators, the hindrances to their progress diminished the possibility of the task being ready by the reopening of Parliament in July. Then in March, their prospects changed when a nearby cellar became available for hire, located directly under the chamber used by the Lords. Percy acquired the cellar from the outgoing merchant, and the conspirators abandoned the mine. Once the gunpowder had been taken into the new cellar and covered, Guy was despatched to Flanders to pass on news to the exiles.
Parliament was prorogued to October, then the 5 November. Fawkes was back in London by the end of August, taking short term residence in the home of Mrs Herbert near the parish of St Clement’s Danes, though he was asked to leave due to his dealings with known Catholics. In October he met with the conspirators to thrash out the details of the plot, including the possibility that known Catholic lords, including Montague, might be saved.