In the latest episode of "Da Vinci's Demons" titled "Liberum Arbitrium," it seems that after capturing Riario, Leonardo finds out that Riario is suffering from dual personality and may harm himself.
According to the synopsis of the episode, after Riario murdered Captain Dragonetti, Leonardo chases him and eventually manages to capture him. However, he has a paranoia attack but quickly recovers from it and continues the chase.
Afterwards, he imprisons Riario in a building where Riario reveals that he no longer wishes to be part of the Labyrinth but believes he is evil beyond redemption.
However, Leonardo tries his best to persuade Riario that things can be turned right, but it seems that Riario has lost all sense of logic and constantly repeats that he can't have redemption.
At the very moment, Leonardo witnesses a horrific transformation in Riario and soon realises that he is possessed by a murderous alter-ego that is manipulating Riario's mind.
In the previous episode titled "Anima Venator," a paranoid Leonardo was shut off from his friends, while an endangered Lucrezia searched for a way to make amends for her sins.
Leonardo escaped from Carlo's prison and met Zoroaster. Together they returned to Florence. Meanwhile, Lucrezia hunted for Lupo Mercuri in order to get information regarding the whereabouts of the Book of Leaves.
Elsewhere, when the authorities discovered that Lorenzo was keeping a group of young women prisoners underneath his house, he was imprisoned alongside them. Besides, Lorenzo was revealed to be working in a Turkish labour camp.
Leonardo experimented with improved explosives designed to counter the Turkish tanks, but found it difficult to damage a captured piece of Turkish armour. Afterwards, it was revealed that the armour had supernatural properties and belonged to Vlad the Impaler.
Late that night, Leonardo found that Captain Dragonetti has been murdered and chased down the killer, who is revealed as Riario. However, while chasing him, Leonardo had another attack of paranoia that left him unconscious.
"Da Vinci's Demons" season 3 episode 6 titled "Liberum Arbitrium" is scheduled to air on 28, November, 2015.