Barefoot and all, actor Will Arnett accepted the challenge on Kimmel's show Tuesday night.
"I feel like I had this nightmare before," Arnett said.
Arnett had to take a deep breath before walking on a bed of Legos. And these were not the big Legos. It's the little ones that hurt the most, as most parents might know.
"The Lego Batman Movie" opens Thursday.
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