Sigismund Dijkstra

Sigismund Dijkstra is the former head of Redanian intelligence and one of the cleverest men on the Continent. He is huge, bald and loud, and dresses in bright colours that make him look like anything but a spy. That is part of the trick. He studied at Oxenfurt Academy, rose to power after exposing his incompetent predecessor to King Vizimir, and for years knew every secret worth knowing in the North.

Dijkstra in The Witcher 3
When Geralt meets him in Novigrad, Dijkstra is living under the name Sigi Reuven and has become one of the city’s four great crime bosses, running his business from a bathhouse. He still has not forgiven Geralt for breaking his leg years ago, but he respects him enough to hire him. In Count Reuven’s Treasure Geralt investigates the theft of his fortune, a heist Dandelion had more to do with than Geralt lets on. Dijkstra also helps Triss smuggle the persecuted mages out of the city, and holds his old flame and enemy Philippa Eilhart captive until Geralt talks him out of his revenge in Blindingly Obvious.

The plot against Radovid and Dijkstra’s fate
Dijkstra’s big comeback is political: together with Vernon Roche and Thaler he plots to assassinate King Radovid in A Deadly Plot and Reason of State. Once the king is dead, Dijkstra turns on his allies to keep fighting Nilfgaard. If Geralt stands with Roche, Dijkstra dies. If Geralt walks away, Dijkstra takes power in Redania and leads the North in the war. See our Witcher 3 endings guide for how this shapes the fate of the whole Continent.

In the books
Dijkstra first appears in Blood of Elves, where he recruits Dandelion as an informant. On Thanedd Island he helps Philippa round up the mages loyal to Nilfgaard, and when he tries to take Ciri to Redania as a political pawn, Geralt knocks him out and breaks his ankle. After King Vizimir’s murder he effectively runs Redania from the regency council, until Philippa turns against him after the Peace of Cintra and he flees the North to escape her assassins.