Three's attempts to hide in the Clubhouse get increasingly tricky in a slapstick comedy of Threes!
Fifteen, while guarding the Clubhouse door, meets up with Three. Almost accidentally revealing whatever she is hiding, Fifteen immediately tells Three to go bird-watching first before entering the meeting. This works, but regardless, Three ends up entering the Clubhouse in order to get her trinoculars. Immediately upon entering, she notices that it's set up like a party; having entered when not told to, Three decides to clone herself with a Magic Mirror and disguise herself as Six.
As the non-clone Three attempts to get out, the clone Three is distracted by a party hat; unfortunately, Six has came, and immediately the clone Three clones another Three as they all become Nine to hide from Six. However, they still can't exit, because Nine is outside, so they hastily disguise as Twelve to hide from him.
Three has soon came up with a plan; disguise as Fifteen and walk out. Unfortunately, they accidentally create five more in the process. As they attempt to get out as Fifteen, the other Threes create another Fifteen, causing the plan to fail as Fifteen is bringing everyone inside. Four of the Threes hide under the table, as the six become Eighteen. When instructed to hide, Eighteen hides behind the table to avoid being noticed.
The real Eighteen soon enters, as Three disguises as Twenty-One in an attempt to cover it up. However, the real Twenty-One arrives, as she soon disguises as Twenty-Four, then Twenty-Seven when the real Twenty-Four arrives. Thirty soon enters, concerned about Three's whereabouts. Three soon reveals herself, briefly surprising herself. She soon realizes the surprise party was for her, the founder of the Three Club. Just as Thirty mentions Three being the only one, the other Threes soon reveal themselves, much to all the other Numberblocks' surprise.
This episode's learning objective is to learn which numbers are multiples of three.
- This is the first appearance of Thirty in Season 8.
- 0, 2, 4, 5, 7, 10, 11, 13, 14, 16, 17, 19, 20, 22, 23, 25, 26, 28 and 29 are absent from this episode.
- This marks the eighth time 2 is absent during Season 7+.
- This episode once had the Circus of Threes thumbnail.
- This is the second episode to feature a treehouse, and the first to feature the "Threehouse"
- There is an error: when 6-30 say “Made of-” and “Ten Threes?!”, Twenty-Seven doesn't have her mask.
- The only non-multiples of three to appear are One and Eight.
- This episode is the 2nd episode to be about a single club. The 1st is Square Club
- Some of the shoes were used in Two times Shoe Shop.