Two things to note: don’t mess with Helena’s babies, and when trying to solve a mystery, make sure the target in question isn’t a relative because things can get quite complicated.

The episode begins with S, Felix, and Sarah arriving at Mrs. S’s old neighborhood.  They head inside and S asks for a man named Terry, who is in the back.  The three meet Terry, played by Daniel Fathers, who is the man that helped S find Sarah and Felix 20 years ago.  He delivers a gun to S, as there’s only one way for this to go down: she intends to kill the Castor Original.

Dr. Coady gives Rudy an examination similar to the one we saw Seth subjected to, but Rudy isn’t able to complete it.  He wonders how long he has, and Coady responds that the best cryptographers are working to crack the Duncan code.

At House Hendrix, Helena shows Gemma a few too dangerous, but effective moves for her karate.  The fact that Gemma is small should not be a disadvantage- use it as a weapon.  Gracie enters and reminds Helena that they don’t do that anymore.

Back at the pub, S and Terry recount how they sprung Sarah from the orphanage and into a safe house.  S shows Terry the number that Rachel translated and Terry realizes that the number means the person was a guest of her majesty’s: a prisoner’s number.  Only the older folks have this kind of number since the numbering system was changed in the 1980s.  Terry promises to get in touch with a friend to find a name for this person.

As Alison prepares for campaign work, Gracie enters to let her know that she has a doctor’s appointment.  That’s fine.  Alison, though, is worried about Donnie.

Donnie, however, is still at Bubbles, examining his battered face in a mirror.  He receives a call from Alison and explains that he just went for a run.  However, he never came to bed, which he blames on sinuses, so he slept on the couch.  Alison is convinced, but she’ll need Donnie to stop by the store to pick up some things while she goes on the trail.

He soon gets a visit from Lionel, who has showed up to collect the pills because Pouchy wants them.  Donnie doesn’t know where they are, so Lionel collects a consolation prize: a very familiar looking tank of frozen nitrogen.  He decides to take this until Pouchy’s supply is returned.

Over at Shay’s, Cosima goes through the files that Delphine gave her before Shay enters.  While Shay tries to get romantic, Cosima leaves, saying that she has final paperwork to finish.

She heads to Scott’s place, and Scott doesn’t find anything that confirms Shay is a spy.  Even still, she did spot the book and mentioned that Cosima mentioned Sarah in her sleep.  Cosima, though, doesn’t sleep-talk.  How she knows what she does in her sleep is another thing.  But also, when Rudy showed up, he knew that Cosima was sick, which Shay also knew.  Cosima realizes that she’s endangered everyone close to her, so now she has to get ready to eat shit.  Gross.

Back on the other side of the world, S reunites with some members of her old band, who knew she was there because Trudy called.  She recognized S’s photo from behind the bar.  Yep.  Turns out that S used to light the place up every Friday night.  S then takes to the stage for a song.

As this happens, Terry returns home, but finds Ferdinand and another man waiting for him.  Turns out that Terry was supposed to call Ferdinand if Mrs. S arrived.  Ferdinand is particularly interested that S showed up along with Sarah and Felix.  Ferdinand’s companion subjects Terry to a harsh ass-beating.

After the performance, Felix pals around with the guys while Sarah and Mrs. S talk their next move. S still plans to take care of the Castor Original through killing.  After all, Castor is sterilizing women.  They cannot let this happen.  She tries getting in touch with Terry, but he’s being tortured right now, so he can’t take a minute to answer the phone.

Helena is busy in the Hendrix garage when Gracie arrives to let her know that she’s leaving for her doctor’s appointment.  The two hug deeply and Gracie leaves.

Following this, Helena spots Donnie returning and sees his roughed up face.  He blames it on jogging, but Helena is smarter than that.  Donnie tells Helena to not tell Alison, as she’s got enough on her plate.

She fixes up Donnie’s face with a cream that the nuns used after they used to beat the demons out of kids.  Donnie regrets his recent decisions, but Helena reminds him that he’s doing this for his family.  Donnie agrees, but now he has to retrieve what was taken, including that tank from under the counter.  Helena, knowing the contents of that tank are her frozen eggs, intends to handle this, but Donnie puts his foot down and tells her that this is a dad decision for the family- and Helena is part of that now.

Cosima’s plan of eating shit will have to wait.  She heads to DYAD and meets with Delphine, who thinks that Cosima has come to confirm that Shay is a Castor mole.  Cosima admits that some things don’t line up, and while Delphine doesn’t intend to help someone who resigned one episode ago, Cosima reminds her that they’re in this bullshit together and need Castor gone.  Cosima then reveals that Sarah is in London to find the Castor Original.  If Castor translated the book, they could be on her heels.  Delphine needs to know who gave Castor the book.

S, Felix, and Sarah find a badly beaten Terry, who tells S that he kept his mouth shut.  He only gave useless bits of information to keep the others at bay.  He then whispers something to S that we don’t get to hear, but it’s enough to get S’s attention.  As Terry dies, S decides that it’s time to go home, as they’ve lost their advantage.  She gives Sarah the gun and tells the two to wait for her at the pub.

Outside, though, Sarah has no intention.  She swiped Terry’s phone and goes through the numbers, eventually finding one that had been called twice today.  She calls the number under the guise of S. The man receiving the call says to meet her at the square in one hour- he’ll send someone.

At said square, Felix and Sarah wait when a man pulls up in a cab.  He beckons the two inside.

Donnie and Helena arrive at the warehouse that Pouchy occupies.  Donnie heads in with the bins, but also tells Pouchy that he’ll need that oxygen tank, as it’s private, even though he originally didn’t know what was inside.  Soon enough, though, the tank is returned.  Donnie then asks if he and Alison can be reimbursed for the pills as well.  Pouchy and his crew find that hilarious.

However, Helena soon enters as Alison and hears Luisa remind Donnie that they know where his family leaves.  Whoops.  Luisa just threatened babies.  As Helena’s theme kicks in, she pushes Donnie out of the warehouse and prepares to take care of business.

Delphine and two men come to Shay’s place unannounced.  Delphine tells Shay to remove her shoes so the two of them can talk.  She then also draws back the blinds.

Overseas, the taxi stops and the driver manhandles Felix for a bit before telling Sarah that he knows she isn’t Mrs. S.  Sarah admits that she and Felix are S’s foster children, and the man helped track the two down some 20 years ago.  Sarah now recognizes the man as Kassov, played by Nigel Bennett.  Kassov’s friend in the parole service found the name corresponding to the prison number: Malone.  They entered in 1978 for aggravated homicide and were paroled in 2007.  Luckily, there’s a current address.

A bloody Helena emerges from the warehouse with a bag containing a giant refund for Alison and Donnie.

Back at House Hendrix, Helena cleans up while Alison comes home surprised at both Donnie’s face and their sudden cash influx.

Shay insists that she is not a spy, regardless of her living situation and income, both of which Delphine thinks are a result of Castor money.  She runs water in the tub, pulls out a razor, and tells Shay the story of a girl at her boarding school who attempted suicide by slitting her wrists in a bathtub.  It didn’t work, though.  She should have cut the metatarsal arteries on the top of her feet too.

As this happens, Cosima receives a phone call from Gracie, who thanks everyone for their kindness and then apologizes for what she’s done, as she was told that she could help save Mark.  Cosima calls Delphine and lets her know that Shay didn’t take the book after all. She’s not the Castor mole.

Felix, Sarah, and Kassov arrive at the address of the Castor Original.  While Felix waits outside, Sarah heads inside.

As Kassov heads off, he makes a call when he gets a surprise visit from Ferdinand, who calls Delphine about the secrets being kept from Topside.  Last Ferdinand saw Sarah, she was locked up at DYAD.  Maybe it’s time to talk and balance out the leverage Delphine has on Ferdinand over Rachel.  Oh, and Kassov’s dead now.

Sarah enters the location and flips through mail when she eventually comes face to face with not a man, but a woman: Kendall Malone, played by Alison Steadman.  The two almost come to blows until Mrs. S enters the standoff between Sarah and…mother?!

Yep, this is Mrs. S’s mother- imprisoned for killing John Sadler.  S didn’t know the prison number until Terry told her.  But where’s Castor?  Why would Duncan send them to her?

Malone talks: Duncan came through testing inmates for cancer research, but Malone knew better than that.  Duncan did round after round to find a viable donor, and he finally found his male.  Just not where he expected.  Malone knows the donor as well- it’s her!  You see, she absorbed a male twin in the womb when she was formed.  As such, she has two cell lines.

Sarah receives word from Felix that they aren’t alone.  S, though, turns on the gas, as she intends to destroy every shred of DNA in the house.  Yes, Castor must be stopped, but this is S’s mother.  Castor and Leda are siblings, so if Malone has two cell lines, then that means she’s their original as well.  They need her- she’s Leda.

We’re coming up on the season finale and this episode gave us a few twists and misdirects with the revelations.  Some were surprising, while one in particular I still question.

But let’s begin with London: first off, it was great to see S, Sarah, and Felix at ease for once.  For my money, I would like to have seen more scenes at the pub, but that wasn’t the reason they were there.  And yet it was good to watch the three just relax and catch up on old times with S’s old friends.  They’re still enduring so much that a brief respite was necessary, even though it was the calm before the storm that led to Terry’s death.

The reveal of Malone as not just having two cell lines, but also being Mrs. S’s mother makes this a much more personal mission for her.  It puts S in a challenging position because she’s now tasked with possibly killing her own mother.  Based on how the episode doesn’t end with S making a move, we see that this decision is weighing on her and, as Sarah pointed out, they still need Malone.  But I’m convinced that if Sarah hadn’t been there, S probably would have killed Malone.

We haven’t seen Ferdinand for some time, but it looks as if he’s been watching things play out from behind the scenes.  In effect, this puts both him and Rachel back in play for the season finale.

Across the pond, the seeds of Donnie’s friendship with Helena grew in a very gruesome way, but one that makes sense.  Donnie is in a low state right now: he’s lost his job, Alison’s mother still doesn’t like him, and he just received a brutal ass-kicking from Justin.  Needless to say he needs a friend that isn’t his wife.  Helena knows what it’s like to protect those close to you, so I buy their companionship.

But Helena is a bit more protective than Donnie imagined.  When Maslany drops the Alison/Helena act and becomes a killer upon Luisa threatening the children, it’s a brief, but strong transition.  The way Helena says “Did you threaten babies,” coupled with Helena’s theme kicking in, made for a great moment as Helena prepared to take care of business.  Helena doesn’t make for a good Alison, but I chalk that up to the heavy accent.

Even though Helena is bloody, we don’t see what happened.  It’d be ridiculous to assume that she didn’t kill anyone, but even if she did, there’s still Jason Kellerman to deal with.  This is one of the misdirects I’m fine with since, based on where we left Donnie last time and the preview for this very episode, I thought that Helena had committed bloody murder on Jason, but I see that I’m wrong.

Know who else was wrong?  Delphine and Cosima in regards to Shay.  Now we don’t know how wrong they are, but it looks as if she’s at least not the Castor mole.  Therefore we don’t have to deal with any sort of cheap, three-way drama between these characters.  Also, Delphine’s back to just making threats to Shay when she was more than willing to screw with Rachel earlier this season.  Did she hold back out of sympathy for Cosima?  No idea.

The look at Delphine’s face when she realizes that Shay wasn’t the spy is indicative of how much it hurts for the characters to be betrayed by someone they trusted and wouldn’t at all suspect.  Shay just arrived and there’s little to say about her, so it’s natural to cast more suspicion on her than an outcast like Gracie.  Though I’m not a fan of Gracie doing this all to be reunited with Mark.

Side-note, how did Gracie even come into contact with Castor without others noticing or even get a hold of the book?  Did I miss something?  If I’m not mistaken, Scott has the original copy and I don’t recall Gracie ever getting a hand on the photocopies that Scott and Cosima made, so when and how would she have even learned about the importance of the text.  Gracie visited DYAD this season, yes, but that was before Rudy made his move on Scott.  So what am I missing here?

Regardless, “Insolvent Phantom of Tomorrow” set up a lot for the season finale.  Ferdinand is back, S must now determine what to do about the Castor Original, and Gracie’s betrayal has thrown everything off course.  And with Rudy examining similar signs as Seth, Castor will want to get their hands on the original fast.  Should be an interesting finale.