The jigsaw puzzle that Shovel & Pail were working on is a picture of everyone playing musical chairs from Mailbox's birthday. Steve is the only character that doesn't appear in the puzzle.
This is the first episode of Pistas da Blue and the United Kingdom version of Blue's Clues.
When Steve says, "The mail's here!", his voice from late Season 1 (the end of this season) is used.
The Mailtime footage uses the same as the earlier episode A Snowy Day.
Blue makes a whimpering sound after Steve tells her that he will play hide and seek again.