'The Strain' season 3 episode 5 spoilers: Setrakian breaks the Lumen's code; is victory over the Master at hand?

This week's episode of "The Strain" combined strokes of madness with the most promising breakthroughs of the season.
This made Professor Abraham Setrakian (David Bradley) question the significance of their crusade: were they really fighting off the infection or were they just delaying a foregone conclusion?
The professor and the Born, Mr. Quinlan (Rupert Penry-Jones), had been leafing through photocopied pages of the Occido Lumen in search of a way to get rid of the Master for good and put an end to the strigoi plague once and for all. Their somber scenes were interwoven with flashbacks to Amsterdam in the year 1972 when a younger Setrakian (Jim Watson) used the Lumen to bait Thomas Eichhorst (Richard Sammel) and avenge himself.
He instead encountered Dr. Dreverhaven (Nigel Bennett), who disguised himself under the name Kruger, and did to him what he claimed to have done when Eichhorst visited him in prison during season 1. He chopped off the Nazi doctor's limbs, locked him in a box, and dumped him into the icy North Sea alive but severely incapacitated.
Presently, a comment made by Quinlan about how the Lumen naturally repelled strigoi because of its silver bindings, Setrakian broke the secret of the Lumen. He took the book to the rooftop and raised one of its pages to the sunlight, the strongest strigoi-repellant. It seemed that whoever wrote the Lumen wanted to make sure that no strigoi was ever going to read what was really written on the book's pages.
The Lumen revealed that an earlier plague had successfully been confined in a "sarcophagus lined with an alloy of silver and lead." This should keep the crimson worm and its host locked in for eternity. But before they could do this, they would first need to figure out the Master's new host.
This prompted Setrakian to make an alliance with the dying Eldritch Palmer (Jonathan Hyde), who was committed to find out the Master's new identity in exchange for a dose of the White. Palmer's last conversation with Eichhorst about overseeing the docking of an important shipment for the Master saw the elderly billionaire's resolve to serve the strigoi's cause seemingly wavering. He had waited long enough for something that he now knew was never going to come.
Meanwhile, Vasiliy Fet (Kevin Durand) tracked a strigoi down into the sewers of Manhattan and saw thousands of strigoi nesting there. Dr. Eph Goodweather (Corey Stoll) and Dutch Velders (Ruta Gedmintas) figured out a way to cut through the communication network that bond the entire strigoi population to the Master.
However, it quickly failed when the Master found a way to get around the interference and reclaim a disoriented strigoi's mind mere minutes after their new weapon was turned on.
The next episode of "The Strain" will find Fet and councilwoman Justine Feraldo (Samantha Mathis) leading an assault on the strigoi in the Manhattan sewers. Titled "The Battle of Central Park," the episode will also show what has become of Gus Elizalde (Miguel Gomez) and Angel Hurtado (JoaquÃn CosÃo).
The official trailer also shows a hoard of strigoi breaking out into Central Park, seemingly hinting on a specially bloody, action-packed episode.
"The Strain" airs on Sundays at 10 p.m. EDT on FX and streams anytime on FX Now.