NOC +10

video intro

On March 6th, 2015, a YouTube channel named "Noc +10" was created. Since that day, this channel is uploading some really darkly mysterious videos. I will start saying something about the name of this channel, which is pretty odd, indeed: searching on Google for "NOC +10" you can easily find out that it may refer to the Naval Operation Concept 2010, also represented with the acronym "NOC 10".

1. First contact - March 7, 2015

0101 0101 0000 0001

first video

The first video uploaded by Noc +10 on March 7th 2015, is entitled 0101 0101 0000 0001: this immediately lets us think of some sort of binary code. It's divided in blocks of four bits, but we do not know its meaning. This video is composed by an odd old-oscilloscope-like display showing some distorted letters and words. Let's break it down:

  • It starts displaying the string NOC+10, with a background piano music, which is easily recognizable: it's the Nocturne Op. 27 No. 1 in C# minor by Fryderyk Chopin.
  • The screen goes black for a bit, the music stops, and a low-tone noise starts: the word START appears.
  • A series of letters is displayed, spelled by a female computerized voice: JKnjGvPaITB, preceded by the string ?v=.
  • When the voice finishes spelling the letters, the word END appears, and the video stops after a few seconds.

Looking at the string ?v=JKnjGvPaITB, we can easily think of an ID of some YouTube video, but the string itself is encrypted, and it doesn't exist a video with such ID. By the way, applying the famous Caesar cipher to this ID we can decypher it and find the ID GHkgDsMxFQY, which is a valid YouTube video ID.

A lot of other questions came to my mind watching this video: is "Noc" related to "Nocturne" in some way? What does the song mean? Etc.

2. First hidden video - March 7, 2015

0101 0101 0000 0010

second video

The ID found on the first video leads us to this unlisted video, uploaded earlier in the same day by the same channel, entitled 0101 0101 0000 0010. The first thing we notice is that the name of the video is almost equal to the previous one, but actually the last 4 bits are different: 0010. The video title changed from ending with 0001 to ending with 0010: it's clear that the two names of these videos are consecutive binary numbers. Let's see what's inside this second video as well:

  • The video starts with an high frequency noise, and the string NOC+10 is displayed.

  • Then a sudden cut of the video brings us to a long string of apparently random uppercase letters, ending with a bunch of zeros:


The same background music is played alongside with the same female voice spelling this sequence of letters.

  • The video ends a few seconds after the voice has finished spelling all the code.

Applying the Caesar cypher again to the code, we can decipher it:


0000000000000000000000 -> These zeros don't seem to have any meaning

Splitting the code in the right parts, we can distinguish a sort of doggerel, which says:

Oh Helen had a steam boat

The steam boat had a bell

When Helen went to heaven

The steam boat went to hell

This rhymes, particularly the first verse, make us think about the Miss Susie american schoolyard rhyme, maybe a variation of it? Looking on Wikipedia on the Miss Susie page, we can find a linked article: SS Sultana tragedy (1865), the greatest maritime disaster in United States history. Well, let's say it: this looks freaking mysterious and gloomy!

3. Second contact - March 12, 2015

0101 0101 0000 0011

third video

A third video, this time public, is uploaded by Noc +10 five days after the last one, and its title is 0101 0101 0000 0011. If we had a suspect of the names of the videos being consecutive binary numbers, now it's clear! Again, let's analyse this third video like we did with the previous ones:

  • It begins with the usual NOC+10 string, with the same Chopin music in the background.

  • A long string of numbers and letters is displayed on the screen:


This makes us think about some sort of hexadecimal string, because the letters which appear in this string do not overcome the letter F, which is the greatest valid hexadecimal digit.

  • A male voice makes 16 equal and unrecognizable sounds while the above string is displayed on the screen, and the video ends: this confirms our thesis about the hexadecimal string.

Applying the Caesar cypher doesn't seem to work this time, but I tried translating it from hexadecimal character pairs to ASCII characters, and the result is even creepier than the previous one:


This seems to be some text alternated with two-character strings inserted to split the words. The result, removing the exceeding characters is:

Hello world helen I wait

But what about the removed characters? They look familiar: m2AfQVy276Y, YES! They represent another YouTube video ID!

4. Second hidden video - March 12, 2015

0101 0101 0000 0100

fourth video 1 fourth video 2 fourth video 3

The fourth video, found with the ID extracted from the third, is unlisted, and has been uploaded by Noc +10 earlier in the same day of the previous one. Its title is 0101 0101 0000 0100. These consecutive binary numbers keep going on. This video also comes with a lot more of information than the others:

  • It begins with the same NOC+10 introduction, the same Chopin music is played.

  • A video cut shows another frame with some text which doesn't seem to be encrypted this time:

     SYSTEM 00010 ALIVE

Another song begins to play: looks like an old song from the '70s.

  • Then a longer, more detailed text:

  • Now the phrase THERE'S ANOTHER MOTHER TO SLEEP HERE appears, and a male voice spells the letters L-I-O-U-Y, then the video ends.

This video seems to be the most important so far: it's clearly full of connections and riddles to solve. It also leads to a large amount of other questions:

  • What are these SYSTEMs referring to?
  • Are these SECTORs part of a ship? Maybe the SS Sultana?
  • What does LIOUY mean?
  • Maybe "another sleeping mother" means another deceased system?
  • Do these two screens have anything to do with the SS Sultana tragedy?

Let's see if we can answer some of them:

  • The string LIOUY was used as an old cablegram Commercial Code, meaning "Why do you not answer my question?".

  • A partial anagram of the phrase THERE'S ANOTHER MOTHER TO SLEEP HERE gives us:

  • It also looks like the famous SS Sultana tragedy is connected to these last videos. Quoting from the Wikipedia page (linked above):

[...] Near 2:00 in the morning on April 27, 1865, when the Sultana was just seven miles north of Memphis, her boilers suddenly exploded. First one boiler exploded, followed a split second later by two more. The cause of the explosion was too much pressure and low water in the boilers. There was reason to believe allowable working steam pressure was exceeded in an attempt to overcome the spring river current. The enormous explosion flung some of the passengers on deck into the water, and destroyed a large section of the boat. [...]

As this story goes on, I'm more and more inclined to think that these SYSYEMs and SECTORs are referring to the SS Sultana.

5. Third contact - March 19, 2015

0101 0101 0000 0101

fifth video

A fifth video is uploaded by Noc +10 seven days after the previous one. This video, entitled 0101 0101 0000 0101, is the third public video, and it has been uploaded on March 19th.


  • Same song and NOC+10 string.

  • A female voice emits four equal and incomprehensible sounds, and a code is displayed on the sceen:

     A oYzXqoELKjE 14

The female voice, if played backwards, seems to be pronouncing P.I., you can listen to it here*link may expire. May these two letters refer to $\pi$ (irrational number Pi)?

The code provided by this video seems to be containing another YouTube video ID, which is oYzXqoELKjE, but there's no video with such ID. Also applying the Caesar cypher to it doesn't provide any valid video ID. Maybe there's some hidden information in the other three characters A 14, some information about how to decypher the ID?

Common points

All the videos begin with the same introduction. All the video titles are represented by an increasing binary number divided in 4 blocks of 4 bits. If we translate the numbers into decimal notation we obtain the numbers 5501, 5502, 5503, etc. It looks like the sequence of the video public settings is: public, unlisted, public, unlisted, etc. All the unlisted videos were found decoding data provided by the previous public videos, this makes us believe there's a sixth hidden video which has got to be found analysing the last video's data.

Can you crack the last video's code and find the ID of the next one?


This is a short summary which synthesizes the developments since the first video was found:

#1 0101 0101 0000 0001 - 2015/07/03 - public
 |- Video URL: youtube.com/watch?v=NCAUPuXzn4U
 |- Encrypted data: "?v=JKnjGvPaITB"
 |- Decrypted (ROT23): "?v=GHkgDsMxFQY"
 |- The decrypted video ID brings us to video #2
#2 0101 0101 0000 0010 - 2015/07/03 - unlisted
 |- Video URL: youtube.com/watch?v=GHkgDsMxFQY 
 |- Encrypted data: [long, see above]
 |- Decrypted (ROT23): "Helen had a steamboat..." rhymes
 |- Unknown meaning of the decrypted data
#3 0101 0101 0000 0011 - 2015/12/03 - public
 |- Video URL: youtube.com/watch?v=AHtiPxfPSu4
 |- Encrypted data: [long, see above]
 |- Decrypted data (HEX to ASCII): 
 |  |- The phrase "Hello world helen I wait"
 |  |- Another video ID: "m2AfQVy276Y"
 |- Unknown meaning of the phrase
 |- The decrypted video ID brings us to video #4

#4 0101 0101 0000 0100 - 2015/12/03 - unlisted
 |- Video URL: youtube.com/watch?v=m2AfQVy276Y 
 |- Plain data: [very long, see above]
 |- Unknown meaning of the data

#5 0101 0101 0000 0101 - 2015/19/03 - public
 |- Video URL: youtube.com/watch?v=-qrtM4LdHH0 
 |- Encrypted data: "A oYzXqoELKjE 14"
 |- Unknown encryption tecnique
 |- Unknown meaning of the data
------ mystery solved ------
 |- Decryption key:
 |  |- Decimal digits of Pi from 10th to 20th, as suggested by the two hex numbers 'A' and '14'
 |- Decrypted (Gronsfeld Cipher): The video ID "jQqQhlCICfY"

Waiting for other revelations

I spent a bunch of time around this, but didn't succeed in identifying the next video (if there is any). By the way, this series of riddles seems really interesting and challenging to me!

The first 4chan thread about this has been unfortunately archived, but contains a lot of useful information about the first four videos. Another thread has been opened on March 19 2015, relatively to the fifth video, and it may be helpful in order to find more hidden clues.

This chatroom has been created to discuss about the topic and arrange some ideas to find the next video. The chatroom has been frozen for inactivity on May 24th, 2015. By the way you can still read the existing messages.


  • March 20, 2015 - update #1: added a link to a second 4chan thread about the fifth video; added the "common points" section; added a summary of the progress made until now.
  • March 20, 2015 - update #2: added a quote from the SS Sultana Wikipedia page in the fourth video section: it seems to be related to this mystery.
  • March 20, 2015 - update #3: added a link to the chatroom created by Bobson (thanks!). Anyone interested is kindly welcome!
  • March 24, 2015 - update #4: the second 4chan thread has been deleted.
  • April 13, 2015 - update #4: the first 4chan thread has been deleted.
  • October 22, 2015 - update #5: the chatroom has been frozen for inactivity.


I will keep this post active and update it if there is any relevant step forward to the solution of the NOC+10 mystery.
The next part of the mystery is being investigated in this thread: The Mystery of Noc +10, Part 2

  • 4
    $\begingroup$ This sounds like an ARG not unlike Cicada 3301. $\endgroup$
    – user88
    Mar 20, 2015 at 2:45
  • 1
    $\begingroup$ 01010101 is 85 in binary, which is U in ASCII. The rest is just a binary counter of the section number. $\endgroup$
    – user88
    Mar 20, 2015 at 2:47
  • 2
    $\begingroup$ An excellently written question! Thanks for transcribing all the relevant bits so we don't have to wade through the videos. $\endgroup$
    – xnor
    Mar 20, 2015 at 5:29
  • 2
    $\begingroup$ @xnor thank you :) it took a bit of time, but I knew it was better to write all the relevant parts down. This mistery is really challenging! $\endgroup$ Mar 20, 2015 at 6:48
  • 4
    $\begingroup$ I preemptively created a chat room for this, and I'm going to dump a few things I tried in there. Feel free to edit it into the question, and/or come by and comment. $\endgroup$
    – Bobson
    Mar 20, 2015 at 19:57

2 Answers 2



Here's the solution! Let's start from the encrypted string:

A oYzXqoELKjE 14

The characters at the beginning and at the end of it suggest us something: they're hexadecimal numbers, and if we convert them to decimal we can see that $A_{16} = 10_{10}$ and $14_{16} = 20_{10}$.

Now, the reversed audio suggests that $\pi$ is involved in the answer, indeed it is. We'll consider its decimal digits, more precisely the ones between the 10th and the 20th (inclusive): they are 58979323846.

Now, applying the Gronsfeld cipher to the encrypted string, and using the extracted digits as the encryption key, we can decode the video ID:

Encrypted:  oYzXqoELKjE - 
Shift by:   58979323846 =
Decrypted:  jQqQhlCICfY

And we got it! Here's the URL:


6. Third hidden video - March 19, 2015

0101 0101 0000 0110

sixth video

The video itself consists of the usual NOC+10 intro, though the sound is distorted. Then, a text (transcribed below, with spacing intact) is displayed with a static noise, followed by a muffled explosion of some kind, which triggers an alarm bell (likely a ship's bell). The video ends right after another muffled explosion.

      16.125628 147.681617

These information still make us believe in something related to a ship, a maritime tragedy. The numbers displayed seem to be a pair coordinates, but the presumed location, which is 16°07'32.3"N, 147°40'53.8"E, doesn't seem to be somewhere relevant but in the middle of the Pacific ocean, somewhere near Northen Mariana Islands. To be specific, the coordinates are precisely at the bottom of the Mariana Trench. The significance of this placement is unknown but seems unlikely to be coincidental.


Still, the presence of words like "assistance" or "system deceased", together with the maritime theme, makes us think of a naval tragedy (maybe a sunken ship).

  • $\begingroup$ I need an answer with a good explaination, I'll wait some more time before accepting one $\endgroup$ Mar 21, 2015 at 18:54
  • 1
    $\begingroup$ well that's an epic solution, I don't know how I didn't think of something like that! I'll edit and accept this answer when I'm back home monday. $\endgroup$ Mar 21, 2015 at 21:33
  • $\begingroup$ @MarcoBonelli - Before you accept, you might want to consider what you'll do when video #7 is posted. You can make a new post that refers back to this one for background, or award leoll2 a bounty for his excellent deduction, but leave the question unanswered until the meta-mystery is solved. There might be more options, too - those two are just what I can think of off hand. $\endgroup$
    – Bobson
    Mar 23, 2015 at 0:57
  • $\begingroup$ @Bobson excellent deduction = 4chan ahahah, by the way I'll make another post $\endgroup$ Mar 23, 2015 at 6:32
  • $\begingroup$ @Bobson Answers can be unaccepted later if required - it's quite common on puzzle with the "open-ended" tag, for instance. $\endgroup$ Mar 25, 2015 at 12:30

16.125628, 147.681617 are coordinates, leading to Guam, UTC +10 [NOC +10]. This must be potentially a distress signal!

  • $\begingroup$ I doubt anyone's sending a distress signal from the bottom of the Mariana trench. :/ $\endgroup$
    – Taconut
    Mar 22, 2015 at 23:34

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