Here's a transcript of the audio log Poirot posted on his blog:
Poirot: Hercule Poirot, log dot nineteen October, 4:00 in the afternoon. I speak English for the courtesy of Mr. Administrator. The subject is Benjamin Barker, […?] of a modern psychoanalyst of some kind. The subject lives in a [struggles with the word “co-op”]… *scoffs* He lives in a cooperative on the outskirts of Boston. As I speak, I have entered into the “coop”… The subject is not in the building, I am observing his belongings in his… er, it is not a room; it is a [possible?] bunk bed. It is rather sparse, I will admit. Everything is terribly old-fashioned, yet this man is in his thirties, which is strange. My […?] has a [mantle?]. It has a pocket-sized portrait of a young woman, beautiful […?], lovely choice. Another… sister? Too old to be a daughter, I imagine… Hmmm… below it is a note envelope. This is strange… it is written in old pen with a broken wax seal. […?], it ought to be an historical document, but it is not yellowed or worn as such. The paper seems to be no more than fifteen or twenty years old… Perhaps… hmmm, in here… There is a leather pouch, I open it, and I review a collection of… old fashioned razor blades. Hmmm… there is one blade missing from the pouch… I wonder if he has it.
Poirot: Hm? Un moment, there is movement coming from the dresser. *crashing*
Todd: Tell me who you are, tell me who you are! You’re the one who’s been following me around, you and that horrible dead creature on your face!
Poirot: I am proud… of my moustache –
Todd: Tell. Me. Who. You. Are.
Poirot: Okay… okay… my name is Hercule Poirot. I am an inspector.
Todd: An inspector? An inspector of what?
Poirot: Of murderers, Mr. Barker.
Todd: …What exactly have you heard?
Poirot: Honestly… very little. I was told only that you had confessed to a series of murders, which is unlikely for you to have committed, and I was asked to investigate you so that other people could determine if you were psychotic. But I know much more, Mr. Barker.
Todd: *threateningly* What. Do you. Mean?
Poirot: Tell me, Mr. Barker, have you ever served in the military?
Todd: What? No.
Poirot: That is too bad. I wish you had told me otherwise, because I know from the way you look at me coldly in the eye. I do not need to look at the razor you placed on the […? Could be “back”] of my neck, that I am not the first “nonne” [“man”] on whose neck you’ve placed a blade.
Todd: And what if it’s not? What’s that to you?
Poirot: I do not judge, Mr. Barker. I listen. It is you, on the other hand, who will be the judge of Hercule Poirot’s life, and whether or not you are the killer I see in your eyes.
[Both men mutter something indistinguishable. Afterwards, Todd appears to be breathing heavily.]
Todd: M’seur, why are you looking for me? You can’t possibly know anything about me!
Poirot: In fact you are right, Mr. Barker. But I would like to know about you.
Todd: It’s no use. It makes no sense. It all sounds mad. Even that woman Lawson thinks I’m mad.
Poirot: Au contraire, M’seur. I do not think you’re mad, and I expected a madman, but I found a mystery, and I would like to solve it.
Todd: What makes you think you can do that?
Poirot: Because, although I could not answer, I can at least see the question, Mr. Barker. Your razor blades, they are old fashioned, nothing like the modern day flat things. Yet, they do not seem antiques; they are old, but not ancient. They are mostly silver as well, I believe. That would be quite expensive. A most unusual luxury. Yet you, you are living in a bunk in a “coop”, by the charity of others, not the sort who could have bought these items. How, then, did you come by them? Perhaps one may think that, as a murderer[?], you could also be a thief, that you simply stole them. But a thief would… just pawn silver, no? [pause] Or perhaps they were an heirloom, passed through the generations, and had sentimental value […?], is all. But either possibility would be more likely if it didn’t have a […?] specific to your […?]. [Barber?] Benjamin Barker. That is too great a coincidence. Perhaps they were your father’s, and you shared his name as son. Perhaps. But even then, it would seem the blades are too… Therefore, I conclude they were purchased as an eccentric luxury by you OR a loved one in better times before your hard luck fell upon you. […?] is the best option, no? But that, er, does explain the crest. Why the portrait, the clothes, and everything about you seems to come from a period play. So, that is the question, that is what I want to know, and I ask: Who are you, Benjamin Barker?
Todd: I… am Benjamin Barker no longer. That man died. He was too naïve to stay alive in the black pit of London.
Poirot: And who are you now?
Todd: I am called Sweeney. Sweeney Todd. These blades, they were a gift from my wife, Lucy Barker.
Poirot: She is in the portrait, no?
Todd: Yes. *tearfully* She was so beautiful. So innocent. We were so happy. When she was pregnant with our daughter Johanna, she went down to None[?] Day’s races. Oh, they were expensive, but we were hopeful. But it couldn’t last, because of that judge! Judge Turpin, a criminal magistrate in old [Bailey?]. He was consumed with Lucy’s innocence. He sent me to Australia on false charges, and forced himself on my beautiful, faithful Lucy! *sobs* Mrs. Lovett told me everything when I returned to my old house and shop. Everything just as it was, frozen in time, except all the life and light had gone out of it. Turpin drove Lucy to take her own life! And… *sobs* Poor Johanna… [pause] From that day on, I was no longer Benjamin Barker. I was Todd, the man who swears vengeance on the wicked and those who stand in the way of justice. My razor will. Be. Their. Justice. At least, until…
Poirot: Until what?
Todd: Until… some weeks ago, I don’t know… suddenly I was swept into this time, I-I-I had nothing, not even a place to live. Then I was found by these people, and they brought me here, housed me, fed me, clothed me, gave me work to do… I’ve even been giving haircuts, and they speak of the same craving for just and right, but… tempered by others for peace. And I began to think, maybe I can start again. Maybe the light can come back. Maybe Benjamin… can come back.
Poirot: So that is it, you are in a different time. No one will ever connect you to your crimes. And live in this enlightened time with all of your [good friends/comforts]. No consequence.
Todd: Well… I wouldn’t –
Poirot: [Sounds like French for “Despicable”]! I met so many men and women like YOU, who are keen to play the vigilante when they kill, but when the law comes to them, they fly like the wind! I devoted my life to the law. I KNOW it is not perfect, but it is better than this, these punishers picking themselves and the criminals to punish! Vengeance without structure is wicked! It blinds us, makes us justify our own evil, and neglect the good that lies before us.
Todd: *sobbing* What do you want?
Poirot: […?] Why, your wife. I believe she is still alive.
Todd: *disbelieving laughter*
Todd: You think yourself very clever – you, with your French manners and that fungus growing on your face. How I would love to trim that into oblivion, Monsieur –!
Poirot: This moustache is unique! You would not BEGIN to understand it.
Todd: But I AM a barber, I know moustaches. I could take it off right now for you –
Poirot: I never asked for your hairstyle advice.
Todd: …I’ll give you much more than that if you don’t start explaining what you said about my wife.
Poirot: Your house, it was uninhabited since you left?
Todd: No one else lived there, that’s right. Everything was… just as I left it, shop and house and all, dusty, dusty and dark. But empty.
Poirot: Was it a particular [“mon”?] this livable place?
Todd: N-no, it was a charming space before.
Poirot: Then why did no one else move into the house?
Todd: …Rumor was, it was haunted.
Poirot: *scoffs* How would they know, if no one moved in after?
Todd: What does that matter –?
Poirot: Fifteen years, Mr. Barker. Somebody must have been interested, particularly in such a slop…
Todd: What are you saying?
Poirot: I am saying either there is a specific reason that Madame Lovett wasn’t selling your house, or… or perhaps… it wasn’t hers to give away.
Todd: And how would you figure that?
Poirot: It would be the case, if one of the original owners was still alive and not delivered to jail.
Todd: No. No, that’s impossible, she poisoned herself!
Poirot: Poison is difficult for the layperson to administer. She could have done it incorrectly…
Todd: B-But she could have just left – she left Johanna dow- behind, she didn’t disappear!
Poirot: After the death of her husband, the raising of a child alone, the exploitation of a judge, and the unsuccessful poisoning of herself, she must have been liable for a total nervous breakdown! By your therapist, you must be surely aware of the hysterical causes.
Todd: Mrs. Lovett…
Poirot: She would have told you, fresh from Australia, that your wife was insane and abandoned your child?
Todd: No! No no, she wouldn’t have left Johanna behind!
Poirot: Mr. Todd!
Todd: Where are the papers? I can’t find them. No, that woman Lawson, she must have them! I must have… I must find! *sound of someone exiting quickly*
Poirot: Todd! Barker! *sighs* Mon dieu… what was he going on about with those papers, unless… *sound of paper shuffling* BARKER?! Are these the papers you were talking about? Mr. Todd or Barker??... MERDE!! [pause] *angrily* Have you heard all of that, Mr. Administrator?
Recent reports have confirmed that this signature is, in fact, not a sea monster.