'Da Vinci's Demons' is finally setting sail for the new world in tonight's episode and it will be interesting to see how the show balances its characters, with Da Vinci and Riario stuck on boats as Florence is under pressure from the fake pope, and there's now movement in the Vatican to possibly dethrone the imposter. And we're less than halfway through the season! It's a busy year.

Pope Sixtus readies for his day as Lupo meets with Lucrezia and shows her and her assassin friend how to enter the Vatican, though Lupo insists she enter alone. Leonardo is informed that -- after 10 days -- they're halfway through their provisions and he must see the former slave crew praying. They're superstitious and fearful they'll sail off the edge of the world. He hopes to be able to teach them the world is round.

As Lorenzo slowly makes his way to the Vatican with Piero, Lucrezia meets with her father and flashes back to meeting him for the first time, which is also when the real Pope was captured by Riario and his brother. The Pope reveals that he stays in the prison as part of an elaborate strategy and asks her to have faith. Riario goes to talk with Nico and gives him some drawing supplies on his quest to convince Nico he's not a bad guy.

Leonardo talks to his shipmates and tries to explain the world is round and convinces them for the most part, and tells them he can prove it if they're willing to wait four hours. Riario asks Nico what he knows about the Book of Leaves, but is interrupted when he's told his ship might crash. Lorenzo and Piero camp, and Lorenzo makes the case for the greatness of Piero's son Leonardo when the two are approached traveling street preachers who know who Lozenzo is and want the money that he's traveling with, which leads to their demise.

Lucrezia and Lupo make their way to a special sword in the Vatican's library which Lucrezia wants to take. Lupo is reluctant, but when a guard shows up, it forces Lupo's hand. He kills the man and sends her off with the sword. Leonardo takes Adana to the deck while everyone else waits nervously. Leonardo promised that Venus would be crescent shaped -- and he was right -- but he thought it would be on one side, and it turns out to be on the other, which leads to some fighting. Eventually Da Vinci's side wins, and his crew wants to kill the former slaves as mutineers, but Da Vinci wants them kept alive and imprisoned. After surviving the preachers, Piero finally admits he has some pride in his son, but he finds it hard to express because of his relationship with Leonardo's mom. The two are then captured by border guards.

Zoroaster chastises Leonardo for putting the former slaves back in chains and suggests that this whole Book of Leaves thing could all be lies, which gives Leo pause.  Zoroaster tells him he can't be surprised that people are offended when the stars don't move as fast as he does, which gives Leonardo an idea: That Venus orbits the sun, not the Earth. He then decides to re-free the slaves, but all but Adana have killed themselves. When they unchain her, she pulls a knife on Zoroaster and asks to be killed. They're able to disarm her, which makes her break down crying. Lucrezia meets with her assassin fiend and plots to go to Constantinople. She then flashes back to Riario granting her and her sister a stay of execution, but the fake Pope kills her sister by breaking her neck. Riario then tells Lucrezia that her adopted family will be killed if she breathes a word of any of this. As Riario's boat sinks, Leonardo mourns the death of the former slaves and suggests that he and Zoroaster need to protect Adana from herself.

There were lots of moving parts in tonight's episode, but it's often best to treat each episode as a chapter in a larger story. Which may explain why Laura Pulver's Clarice was nowhere to be seen. The highlight of the episode was Da Vinci figuring out the solar system, and it's a great moment and sequence, but with the show so split up between all of its characters, it suffers a little from the multiple storyline-itis. Currently the show is tracking at least five plot threads, and though this left out Clarice's, such means that even Leonardo is going to become a supporting player in the ensemble. That may be a problem with the season, and it could be a problem with future adventures, but it wasn't troubling tonight.

The show has set up so many exciting possibilities of where it's going to go next, and "possibilities" is what made this episode exciting, so hopefully the show will stick the landing. But because of this there's also less meat to chew on outside of Leonardo's complicated relationship with the (now mostly dead) former slaves, and Piero's now better defined relationship with his son. This was about putting pieces into place, and now that we're getting to the second half in the season, we're hoping those pieces pay off. Soon, even.

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