The curse on the cape itself - it's easy to understand why a curse that turns the wearer into a vampire would spur him to kill, but why a vampire in the first place? Was it first made for a production of Dracula, before Lewis acquired and cursed it? (Which might explain why, when Frank the Villain of the Week instinctively retreated back in time, accidentally taking Micki and Ryan with him, they went back to around the time the book was written, and the place where Bram Stoker just happens to be living.)
A very plausible theory!
Then there's the clasp, which is specifically the means by which the time travel happens. But as we see at the end with Ryan and Micki you only need a drop or two from those traveling (Ryan gets a dab of blood from his forehead wound, and Micki pricks her finger on the pin of the clasp); no death required. That doesn't sound much like a Vendredi curse, so how did it end up paired with the cloak? Was it a separate, magical item that somehow wound up fastened to the cape? If so, where did it come from?
Good question. We've seen examples of other magical items that weren't artifacts, although they were all still evil in nature or could be used for evil. (A time-travel item activated by blood could still count as the latter, considering the possible dangers of such, if Stable Time Loop, You Already Changed the Past, and other time travel tropes don't apply in this universe.) Perhaps Lewis (or someone else) paired the two together, since the ability to travel through time would both make it easier to find victims to enchant and give the charismatic killer an easy escape route if he gets caught.
Also, how Frank got the cape in the first place. He's just looking for a room to rent, when he sees the cape laid out on the bed, and his potential landlady seems to fall in Love at First Sight with him wearing it and tells him the rhyme that describes the cape and clasp's powers. Was the cape driving her to find it a new wearer, and why couldn't she wear it? If it was associated with a theatrical or cinematic production of Dracula as speculated above, could it be that the curse wouldn't allow a female to wear it, because Dracula is always a man?
This one really is left unexplained. Charisma and dominating the will of others is a common vampiric trait, so it may be that Lewis simply used his curse to turn the cape's wearer into a vampire as the easiest (and most evil, from the Devil's POV) way to give them such powers. But if the cape was associated with Dracula in some way, that could have been what gave Lewis the idea, or influenced the curse to take the form that it did. Either way, that would also explain the landlady's actions, since presumably a power from the Devil would be stronger than any individual vampire, especially if it was associated with Dracula himself.
After Ryan and Micki return, Jack believes from their description that they were in Whitechapel during the late 1880's - the time and place of the Jack the Ripper murders; it's implied that not only did the episode inspire Bram Stoker to write 'Dracula' (in the 1890's), but that Frank's murders were mistaken as the Ripper's killings. However, Jack The Ripper had already been introduced as a separate entity in the canon (the scalpel from "Doctor Jack" was his), and the streetwalker who is Frank's first kill listens to a newsmonger shout a headline about the Ripper killings... so which is it? Or did Frank's murders simply not come to public attention and historical record because everyone was concentrating on Jack the Ripper?
Fridge Brilliance crossed with Shown Their Work: If you read the Wikipedia entry on Jack the Ripper, you'll find that there are only five murders considered canonically to be his by most reputable detectives/Ripperphiles. But there were a number of murders at a later date, one or two before the first of the five, and even a few others around the same time (such as the Torso Murders) which have often been claimed to be Jack's as well, and which have also never been solved. It is believed at least some of them were copycat murders, but others are thought to be completely unrelated. Frank's murders could be an example of some of these.
It's entirely possible that the vampirism, cape, and brooch are all separate issues. We know from other episodes that vampires are a thing that exists in the world. It could be the lady was a vampire that realized the cape could make a man irresistible and set about trying to find the perfect man for her. She turned him into a vampire. Then the brooch was its own source of magic doing the time travel thing.
From "13 O'Clock"
So what happens to the bad guys at the end? They freeze in time... in the middle of the tracks in a busy subway station. Did they just stay there? Could everyone see them? Did subway users see two frozen-in-time people? What happened the next time a train came along?
I was going to say that perhaps only Ryan could see them, because he was the one holding the watch, but Micki saw them too. Plot Hole. (Unless that was due to her latent magic?) That said, it's likely that because the bad guys were frozen in time, they were probably out-of-phase with reality, permanently in that endless moment, so that even if everyone could see them, things in the regular world (like the train) would pass right through them and couldn't even touch them.
From "The Pirate's Promise":
Maybe not a Headscratcher, but an intriguing question nonetheless: as detailed in the main page's The Bad Guy Wins entry, the episode's Greater-Scope Villain, the Ghost of Captain McBride gets exactly what he wanted - a dead descendant of every one of his mutinous crew members. So since the cursed foghorn, from his original ship, was linked specifically to McBride, and worked by summoning his ghost to exchange those dead descendants for gold coins... now that McBride has what he wants, does that mean the curse on the foghorn is broken?
Huh, I never made the connection that the horn was from his ship; was that ever actually stated? Plus, he was a pirate several centuries ago, and the horn looks rather modern to be from that time... In any event, even if it was broken, clearly the trio weren't taking any chances since Micki and Ryan said they were taking it back to the vault at the end.
No. The Foghorn is still cursed, and would, on its own, eventually find its way into the hands of someone else, who would use it for his/her own purposes. Perhaps the Ghost of Captain McBride would still be summoned but this time as a vengeful ghost who tries to kill the one who disturbed his rest (unless, say, the summoner names another to die in his/her place). Also the cursed artifacts have the power to change themselves, their powers and the nature of their curse when given to new owners.
McBride isn't the only wicked pirate who ever carried a grudge to his grave. He may not even be the first one to be summoned by that particular artifact, only the latest.
From “The Playhouse”:
Jack says the police will take it apart and examine it, and that would be their inclination, except for one thing: the artifacts, once cursed, cannot be damaged. How are the police going to account for that?
Maybe it folds up or can be taken apart in sections, with each piece still invulnerable? Otherwise, how did they transport it from the antique store originally?
