Upon the orders of Pope Bonafice VIII (Jim Carter), Landry (Tom Cullen) and Tancrede (Simon Merrells) strive to uncover the whereabouts of the Holy Grail as the plotting behind the royal wedding becomes life-threatening in the upcoming episode of the new historical fiction drama television series "Knightfall."

In the promo for the upcoming installment, Landry and Tancrede can be seen being given a scroll that is assumed to lead to the Holy Grail. They are tasked to discover the vessel and protect it but, their capabilities are questioned when they are asked: "How could you protect the cup that wields the power of God when you do not know what that power is?"

Having used Princess Isabella (Sabrina Bartlett) as a strategic chess piece, the Pope chose to give his approval of a marriage to Catalonia as opposed to Prince Edward of England, which has made Guillaume de Nogaret (Julian Ovenden) upset at the potential loss in power. Now needing the support of Catalonia at their side in a potential war with England, de Nogaret requests support from the Catalonians (Enrique Arce and Marcoz Franz), but the two factions do not exactly see eye to eye about jumping into any kind of conflict with England.

In the previous episode, Pope Boniface arrived in Paris to learn about the whereabouts of the Holy Grail and make Landry Master of the Temple. However, the Pope's unexpected arrival threatened de Nogaret's carefully laid plans to marry King Philip (Ed Stoppard) and Queen Joan's (Olivia Ross) daughter, Princess Isabella to Prince Edward of England. Later, Landry and Parsifal (Bobby Schofield) sought revenge on Roland (Cengiz Dervis), the highwaymen's leader, who murdered Godfrey (Sam Hazeldine) and Marie (Sai Bennett), Parsifal's fiancee, after the farmer came to the Templar master's aid.

"Knightfall" episode 3 entitled "The Black Wolf and the White Wolf" will air on Dec. 20 at 10 p.m. EST on the History Channel.