Sebastian

Animation: The Cat in the Hat (Movie)

Moving to a new town is hard enough without a six-foot cat crashing through your front door. In Warner Bros. Pictures Animation's 2026 feature, Sebastian finds himself at the center of the Cat's most chaotic assignment yet, dragged into a whirlwind of mischief and mayhem alongside his older sister Gabby.

Sebastian’s Role in The Cat in the Hat

Rooted in the unnamed narrator boy from Dr. Seuss’s 1957 classic, Sebastian gets a full identity in this reimagining as Gabby’s younger brother, struggling with the upheaval of relocating to a new town. Where Gabby has older-sibling prickliness, Sebastian carries the kind of wide-open anxiety that makes him both the most vulnerable and the most instantly relatable of the two kids. His first reaction to the Cat’s arrival speaks for itself: a full-throated cry of “stranger danger.” He is, in short, a kid who did not ask for any of this but ends up right at the heart of it anyway. His arc runs parallel to Gabby’s but feels distinctly his own, as the Cat’s increasingly out-of-control scheme forces Sebastian to reckon with a new home he hasn’t been ready to accept.

Who Voices Sebastian in The Cat in the Hat?

Sebastian is voiced by Tiago Martinez, a young actor whose credits include a voice role in DreamWorks’ The Wild Robot, where he played Baby Opossum 2, as well as appearances in the Apple TV+ series For All Mankind. His casting brings a natural, unguarded quality to Sebastian that fits the character’s mix of nerves and reluctant curiosity.

Sebastian Voiced by

English

Tiago Martinez

Tiago Martinez, One of the more active young American actors working across both voice and on-screen roles, Tiago Martinez built…...