Harris donned a Riddler costume, Burtka was The Joker, and 4-year-old twins Gideon and Harper went as Batman and Robin.
Harris posted a picture of his family on Instagram with the caption, "Happy Halloween from Gotham City!"
The actor and his family always go all out on Halloween. Just last year, they dressed up as classic monsters and Alice in Wonderland characters.
What were your favorite celebrity Halloween costumes?
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