The Royals have had three seasons so far which have completed.
Season one summary:
The season may have started out with the family grieving over Prince Robert's apparent suicide, however, by the end of the season we come to learn what really happened to the former king-to-be. He was actually murdered by a Brandon Boone, who confessed his wrongdoing to Eleanor and Jasper during the finale. Why? Because he thinks the secret organization that ordered him to do this is now after him. Looks like the murderer is afraid of becoming the murderee. Speaking of which, Robert wasn't the only member of the monarch to lose his life that year. King Simon was also killed by an unknown assailant. It's unclear whether this hit came from the same organization that enacted Robert's demise, but if it is, then the rest of the family better start watching their backs.
Just when Prince Liam was gearing up to ascend to the throne in his father's stead, Queen Helena publicly revealed that Liam and Eleanor were not Simon's biological children, but rather the product of her secret affair with Alistair (who may or may not have been killed on Lucius' orders in the finale). And while the test results appeared to confirm that he was the father of Liam and Eleanor, we eventually learned that Dr. Cohen never actually tested their blood (it was all part of a scam to help put Cyrus on the throne), which means there's still a very good chance that they really are Simon's true heirs.
Cyrus and Prudence.
This Royal Family maid has not had the greatest working experience at the palace TBH. First, she was sexually harassed by Cyrus "Quid Pro Quo"-style, after he threatened to have her fired if she didn't perform sexual acts. She then attempted to kill him and got caught in the process. But instead of killing her, Cyrus offered her a deal: If she were to start spying on the king, then all would be forgiven. However, the truly shocking detail of her story arc came at the very end of the season when she showed up out of nowhere at the palace and revealed to the now-King Cyrus that she was pregnant with his child.
Jasper and Princess Eleanor(jeleanor).
While it's true that Eleanor and Jasper's relationship has gone through some pretty dark times (like when he was blackmailing her to have sex with him using a nonexistent sex tape), real feelings began to develop from both parties throughout the course of the season. And now that Jasper is helping Eleanor find out the truth behind her brother Robert's death, I have a feeling it'll end up bringing them even closer together.
Prince Liam and Ophelia (Lilia).
Unfortunately, I can't say that same thing about Ophelia and Liam. Though the plan was to originally run away together, Liam decided that it would be best for them to go their separate ways for now, allowing Ophelia to pursue her dreams of becoming a dancer in NYC. But given that Gemma's family sponsors the dance company she was auditioning for, this dream could just as easily turn into her worst nightmare.
It's difficult to include this storyline since we still don't really know anything about what this is or what it means. However, given that this Domino symbol has shown up multiple times (once on a letter, once on a pendant, and once on a flag), I think it's going to become a very important plot development in the near future. Perhaps this is a secret organization that played a hand in Robert and Simon's deaths. (Much like the game, Domino's goal may be to knock down the members of this monarch, one by one.) Either way, considering the look of dread on Queen Helena's face when she sees this logo, it's safe to assume this Royal family's reign is in serious jeopardy.