The Terrible Twos is the thirteenth episode of the first season of Numberblocks.


It's nightime. The Numberblocks are asleep. Four cannot make up his mind whether he can stay up or go to sleep. Four has trouble deciding.


The two Twos become the Terrible Twos!

The Terrible Twos start by tickling One, causing her to laugh. Then they shout "BOO!". Frightened number One bounces on her bed. Next, the Terrible Twos tickle the normal Two. When they shout "BOO!", Two is frightened he separates into two Ones.

Next, the Terrible Twos try to tickle Three, but she wakes up quickly & juggles just before she gets tickled. When the Terrible Twos shout "BOO!", Three separates into three Ones. They chase the Terrible Twos to Four's bed. They shout "BOO!" to themselves, causing them to separate into four Ones.

One remains as one block.


Nine other Ones turn back into Two, Three, and Four. Five wakes up and wonders what the noise was. Four explains that he was the Terrible Twos. The others think that he's joking and go back to bed.


The Terrible Twos call out their name and shush to the camera.


  • 4 stays in a square shape for the entire episode.
  • Before the release of "Once Upon a Time", BlueZoo uploaded a GIF of The Terrible Twos and Four on a white background flying in the air from Peekaboo on Twitter.
  • This is the second episode where One is seen sleeping. The first is Another One.

Running Gags

  • The Terrible Twos tickling Numberblocks 1-3.
  • The Terrible Twos jumpscaring Numberblocks 1-3.


  • When Four yawns and turns into the Terrible Twos, The Twos share four's limbs.


Numberblocks episodes
Here are all the Numberblocks episodes.

Series 1

High Five!

One, Another One, Two, Three, One, Two, Three!, Four, Five, Three Little Pigs, Off We Go, How to Count, Stampolines, The Whole of Me, The Terrible Twos, Holes, Hide and Seek

Ten out of Ten

Six, Seven, Eight, Nine, Ten, Just Add One, Blast Off, Counting Sheep, Double Trouble, The Three Threes, Odds and Evens, Fluffies, The Two Tree, Numberblock Castle, Ten Green Bottles

Series 2

Number Fun

Once Upon A Time, Blockzilla, The Numberblocks Express, Fruit Salad, Zero, Now We Are Six To Ten, Numberblobs, Building Blocks, Peekaboo!, Hiccups, What's the Difference?, Numberblock Rally, Five and Friends, Octoblock to the Rescue!, Ten Again

Fifteen and Friends

Flatland, Pattern Palace, The Legend of Big Tum, Mirror, Mirror, The Wrong Number, Eleven, Twelve, The Way of the Rectangle, Ride the Rays, Block Star, Thirteen, Fourteen, Fifteen, Tween Scenes, Step Squads

Series 3

Season 5

Fifteen's Minute of Fame, On Your Head, Ten's Place, Balancing Bridge, Sixteen, Square Club, Seventeen, Eighteen, Loop the Loop, Nineteen, Twenty, Tall Stories, Flights of Fancy, I Can Count to Twenty, Heist

Season 6

Sign of the Times, Fun Times Fair, The Lair of Shares, Terrible Twosday, Divide and Drive, Twenty-One and On, We're Going on a Square Hunt, Thirty's Big Top, Land of the Giants, Fifty, Sixty's High Score, The Big One, One Hundred, One Thousand and One, More To Explore

Upcoming (confirmed)


Numberblocks Theme Song

Fourth Wall Breaks

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