Spoilers abound. You have been warned. Continue at your own risk.
There has been a lot of hoopla over the end of the Showtime series Penny Dreadful. I, personally, while surprised that it was actually “The End” believed it concluded at a good spot, in a good way, and was actually always planned this way. The writer and creator John Logan had said he planned through 3 seasons back in 2014. And I originally took this to mean that he would write more as each season passed, but I believe with Showtime’s not Game of Thrones-equal ratings, the network’s likely reticence to continue past Vanessa Ives’ death (played by Eva Green, the only actor who was continually praised as the main gem of the show).
During the season 3 finale E3S9, “The Blessed Dark,” the Penny Dreadful twitter went silent. And the next day, the Penny Dreadful Youtube channel released 2 videos of John Logan talking about the end of the show, and the final moments on set. The day after, they started sharing images on their Facebook/Instagram that the end had been “foretold” by quoting past lines from past episodes of the show – I agree with them, and I’ll go more in depth in a moment. And finally, yesterday, the Youtube channel released a video of Eva Green talking about the end, and one more video of John Logan talking about Eva Green’s last scene she filmed for Penny Dreadful (spoiler: it wasn’t her death scene).
Okay, going back into why I should have seen the end coming:
- The introduction of the Penny Dreadful “penny dreadfuls” (aka comics, see
bottom of the post). Why would they need to use another medium for storytelling if the show was going to continue and they would have been able to reveal these stories in flashbacks like they had previously done so? - Vanessa’s debut of the Season. Broken down since Season 2’s end and completely different from
the Miss Ives we know and love from Season 1. You can read more of my love for her character (and the rest of the main cast) here. - Malcolm’s transformation: he was a hard and ruthless man for all of Season 1, still very much the same in Season 2, but Season 3 shows his softer side (even if he does wield a gun in almost all of his scenes).
- Killing “loose ends” (aka characters from previous seasons): Hecate Poole (whom I liked, but many didn’t) and Inspector Rusk (who pissed me off all the time).
- Mr. Lyle’s departure. I never thought he would leave (and I don’t mean that in a sarcastic manner). After surviving Evelyn Poole’s wrath, I assumed he would stick with Vanessa as stoutly as Ethan, Frankenstein, and Malcolm did. But I was wrong. Thankfully, he didn’t die, but it was still a strong indication that this season wouldn’t be the same as the 2 previous ones where he had played an important role in each.
- Revealing the rest of Ethan’s back-story. Besides who/what has been hunting Vanessa, Mr. Chandler’s backstory has perhaps been the show’s most well-kept secret, and to have it all revealed throughout the season, rather than a single puzzle piece at the very end, was a huge tip-off that stuff was changing.
- Frankenstein’s realization that playing God isn’t a good thing. Even though he realized he created a monster in the Creature and Lily by the end of Season 1 and Season 2, respectively, Frankenstein never acknowledged that his resurrection acts were harming people, not merely a means to make his name famous.
- The revelation of Brona’s daughter. Giving back-story for such a complicated and mysterious character normally means they’re going to die in this show. It was true for Van Helsing and Mina Harker. But with Brona/Lily, she doesn’t die. She’s almost “tamed” by Frankenstein and
Jekyll, but eventually goes away, leaving Dorian alone. - Dorian being left alone. He had asked Vanessa to read his future, to which she replied that not everyone has one. And according to Penny Dreadful, he certainly doesn’t. But his “no future” here is better than the literary ending he received from his original creator, author Oscar Wilde.
- The Creature’s family. Just like Brona, his old family is revealed to the audience and then subsequently lost (although differently).
- The introduction of 2 more Dracula characters, a gender-bent: Dr. Seward and crazy Renfield. This connects us back to Season 1, reminding us who the first villain was. Another connection to Season 1 is Ethan Chandler mentioning “Night Work” and maybe what would happen if he hadn’t joined them back then in S3E7, “Ebb Tide”)
- Speaking of the first villain, the introduction of Dracula (S3E2, “Predators Near and Far”) is probably the biggest sign that Season 3 would be the last. He’s been the big villain since Season 1, even if they never said his name, and for him to appear in the flesh meant that Season 3 was the end game, even though I might not have realized it. One might ask, “Wait, what about Lucifer from Season 2? He’s the Devil, isn’t he the big baddie?” Well, no. Not necessarily. The tarot card of The Devil in Vanessa Ives’ deck shows a creature with wings, carrying a bat. Now, you could say that represents both Lucifer and Dracula (who are brothers—Dracula is older, by the way—as is revealed in S2E8, “Memento Mori” and S3E4, “A Blade of Grass”), but if you remember S2E8, you’ll know that Dracula was also an angel cast out of Heaven. So, the wings on the creature/man on the card
is actually likely Dracula and not Lucifer. - I’m going to group all the “foretold” images shared by the Penny Dreadful social media for #10 below because as seen in reason #9, a lot of what happened was merely closing the plot circle that John Logan began in Season 1. My captions give more context than the season and episode numbers at the top of each image.
You can see many of these same points echoed in this IGN video review. But, here is FoundFlix’s take on the 2-part finale which, like mine, is much more positive than 90% of the internet’s, quiet frankly, explosive response.
Also, completely random note: you may want to purchase the haunting music of Penny Dreadful.
When we first meet Mr. Lyle and he deciphers the hieroglyphics on the vampire/creature Sir Malcolm kills in S1E1, “Night Work” 
A vague, prophetic answer given by the show’s new creation Fenton (who acted like Renfield from DRACULA, and who I assumed would be standing in for the original literary character – I was later proved wrong) while being kept prisoner in Sir Malcolm’s basement/dungeon 
A line from a Grand Guignol play witnessed by Vanessa, Ethan, Dorian, and Brona that is reprised to tell Vanessa that Mina is at the theater. I also took it as confirmation that Ethan was a werewolf. It is also now clear that “there cannot be a happy end” referred to the whole show and the werewolf references were also alluding to the fact that Ethan would be the one to kill Vanessa. 
A plea Vanessa told Ethan during a brief lucid moment during her crazy possession in S1E7, “Possession.” He didn’t follow through then, instead opting for an impromptu exorcism (because doesn’t everyone know how to do one – Supernatural fans, I’m looking at you). But now the story came full circle, and he did to fulfill Vanessa’s (reiterated) wish and to save humanity. 
Vanessa to Ethan in Season 2, Episode 7 “Little Scorpion,” expressing her increasing inability to live her dangerous life (and echoing the previous quote from a full season earlier, also the 7th episode)