Contains all three books in the Demon Summoner trilogy.

Apprentice, book one:

The year is 1642. As a decades-long war rages through Central Europe, military field surgeon Martin shares a shocking truth with his apprentice Gustav: Demons are real, and the victims of battle are their reward for fighting for mankind. A reveal that changes everything…

Historical facts combined with elements of fantasy and sprinkled with a good dose of humor.

Journeyman, book two:

The year is 1645. A murderous war has been raging in the Holy Roman Empire for twenty-eight years, and there seems to be no end in sight.

Gustav and his master have been banned from the Black Feldsher Guild and have had to take leave of the Swedish army. In the middle of winter, they roam the battle-scarred land as simple healers, helping the war-weary people. But their enemies are still on their trail.

Martin is still in Saxony with his apprentice. Everything there has been devastated by war. The winter is harsh. People have nothing to eat. Wolves are back on the streets. It's hard to believe how many accidents happen every day.

Master, book three:

After the death of his master, Martin, Gustav is left with nothing. Only Anike is there to console him over the heavy loss. When she asks him to help her possessed father, Gustav realizes that the key to helping her—Martin's Codex Daemonum—makes no sense to him. He must first complete his apprenticeship to be able to decipher the mysterious book. Torstensson finds him a new master, but the man only wants to kill Gustav. A reckless game begins in which everything is at stake.

"Take care of yourselves! Your beautiful Mela won't always be there in time to save you. The real war is just beginning."