(Music plays)

An animated clip shows a big orange X on a blue background. It explodes and letters and numbers come out of it in all directions and float around.

Mathemagician Eric appears on screen. He’s in his mid-twenties. He has short dark brown hair and a beard. He wears a red T-shirt with the show’s logo, blue jeans and red Tennis shoes.

The screen turns red and the logo of the show appears next. It reads "MathXplosion." Meanwhile, cones, cubes and dices float around it.

Kids voices sing a song with lyrics that go
WHAT A HIT
IT'S NOT A TRICK
IT'S MATHXPLOSION
JUST FOR YOU
COOL AND NEW
MATHXPLOSION!

The episode starts with Eric standing in a workroom.

Eric says SHH!
DID YOU KNOW THAT WE CAN
SEND THE KIND OF SECRET
MESSAGES THAT THE ANCIENT
ROMAN ARMY USED MORE THAN
2,000 YEARS AGO?
WOW.

He disappears for a moment and comes back with a golden Roman helmet.

He says HA, HA!
THEY USED SOMETHING CALLED
THE CAESAR BOX CIPHER,
NAMED OFF ROMAN
EMPEROR JULIUS CAESAR.
SEE SECRET MESSAGES APPEAR
AND DISAPPEAR BEFORE
YOUR VERY EYES.
I'LL SHOW YOU
HOW IT WORKS.
BUT FIRST...

He takes a small piece of paper with a word in it. He folds it and spins it and moves it. Once he stops, he reveals the word written in it. It is "Secret."

He says SHH.

Now Eric is ready to start a new project.

He says A CIPHER IS A SET OF
RULES FOR ENCRYPTING AND
DECRYPTING SECRET MESSAGES.
SOME CIPHERS SUBSTITUTE ONE
LETTER FOR ANOTHER, WHILE
OTHERS MOVE LETTERS AROUND.
CAESAR BOX CIPHERS
ARE THE SECOND KIND.
SAY I WANT TO USE THIS
CIPHER TO SEND MY FRIEND A
SECRET MESSAGE.
I TEXT HER AN ENCRYPTED
MESSAGE THAT LOOKS LIKE THIS.

He takes a phone and types a message. A caption on screen shows what the text message should be. It reads "smaeeoppnrpidele."

Next, he says SEND.
WHEN SHE DECRYPTS
IT, IT SAYS...

He shows the correct text written on a paper that appears also as a caption that reads "Send more apple pie."

Eric continues
MY FRIEND'S THE ONLY BAKER
IN TOWN WHO KNOWS THIS
CAESAR BOX CIPHER.
MMM... SECRET PIE.
SORRY.
YOU HAVE TO COUNT THE NUMBER
OF CHARACTERS OR LETTERS IN
CIPHERS, TOO.
IN THE CAESAR BOX CIPHER,
THE NUMBER OF LETTERS IN
THE MESSAGE MUST HAVE A
SQUARE ROOT, WHICH MEANS
YOU CAN MULTIPLY A NUMBER
BY ITSELF TO GET THAT
NUMBER OF LETTERS.
SOUNDS CRAZY, HUH?
NAH, IT'S EASY.
LET ME SHOW YOU.
LET'S SAY MY MESSAGE
HAS 16 CHARACTERS.

The caption of number 16 appears on screen.

Eric continues
WHAT NUMBER MULTIPLIED
BY ITSELF EQUALS 16?
4.

Now the caption changes to "4 times 4 equals 16."

Eric continues
SO I NEED A CIPHER BOX WITH
FOUR ROWS AND FOUR COLUMNS.
HERE IT GOES.

(music plays)

Eric draws a grid.

He says TO ENCRYPT MY MESSAGE,
I'LL WRITE THE MESSAGE
VERTICALLY STARTING
IN THE LEFT COLUMN.

(music plays)

He starts writing the secret message using one box for each single letter. As he types, the letters blink.

Eric says BUT TO SEND IT, I ENTER THE
LETTERS FROM LEFT TO RIGHT
ACROSS ROWS, NOT UP AND
DOWN IN THE COLUMNS.
TO READ OR DECRYPT IT, MY
FRIEND DOES THE SAME THING
IN REVERSE.
SHE MAKES A 4 TIMES 4 TABLE
AND WRITES THE LETTERS IN
COLUMNS STARTING
IN THE UPPER LEFT.
SHE THEN READS IT AND SENDS
BACK HER ENCRYPTED ANSWER.

He looks back at his phone and sighs.

Next, he says I HOPE SHE SOLVES IT SOON.
SECRET MESSAGES
WITH YOUR FRIENDS.
SEND THEM, SOLVE THEM,
SEND BACK NEW ONES.
IT'S NOT MAGIC, IT'S...

He tries to read a secret message, but it looks like he’s not getting it right.

He frowns and says OH, SORRY, THAT
WORD'S ENCRYPTED.
I MEANT, IT'S NOT
MAGIC, IT'S...
MATH.
OF COURSE.
I LOVE THAT.

A big explosion brings the show’s logo back on the screen.

(music plays)

The end credits roll.

Produced by GAPC Entertainment in association with TVOKids.

Copyright GAPC Entertainment (MathPlosion) Incorporated, 2016.