After five-year-old Jack and his mother escape from the enclosed surroundings that Jack has known his entire life, the boy makes a thrilling discovery.

Remember little Jack from Room? The Little Mermaid star looks so different now!

Jacob Tremblay was on the red carpet for The Little Mermaid on Monday night - and he looks so different!

TV & Film Editor

May 16, 2023May 16, 2023, 4:08 PM GMT+1

It is always a shock when we see child stars all grown up - especially when it makes us feel old - and we can’t believe how much Room and Wonder star Jacob Tremblay has grown up!

The youngster became a well-known actor after starring in the Oscar-nominated movie Room alongside Brie Larson, who won Best Actress for her portrayal of a woman who raises her son while they’re both held captive by her kidnapper. Jacob went on to huge success, starring in Wonder, Good Boys and Doctor Sleep - and most recently voiced Flounder in the upcoming live-action version of The Little Mermaid.

WATCH: The Little Mermaid star hails film’s diverse cast as a 'beautiful melting pot'

The actor, now 16, joined his cast mates at the London premiere of the Disney movie on Monday - and he looks so different! Fans were surprised on Twitter, with one writing: "OMG, WHAT? If the stranger things kids make me feel old, Jacob Tremblay gave me my retirement notice."

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Another person added: "I bet that if now you take a photo of Jacob Tremblay next to Brie Larson, he probably is taller than her," while a third posted: "Jacob Tremblay isn’t this little kid anymore???? But that was just yesterday. I feel old."

Jacob Tremblay attends the UK Premiere of "The Little Mermaid" at Odeon Luxe Leicester Square

Others pointed out that Jacob somewhat resembles another Hollywood star, with one person writing: "I need Jacob Tremblay & Timothee Chalamet to play brothers in SOMETHING, like am I tripping or do they look similar??? Plus like the way he's talking idk it just reminds me of how Timothee talks."

Another person added: "Y’all need to stop mentioning Timmy every time Jacob pops into ur tl... he is NOT the next Timothee, he is NOT copying him. They are their own person and i think the comparison needs to end, just appreciate Jacob Tremblay for being Jacob Tremblay."

Speaking about growing up around making the movie, Jacob explained to Variety: "I went into for the audition… I was gonna sing Kiss the Girl. I was very nervous, luckily, I think I was 12 at the time, my voice hadn’t changed yet. If I were going into the audition again, I wouldn’t be able to pull it off I don’t think. My voice would be cracking too much!"

He added: "When we were recording my lines, I’d done animation before with Luca, it was in a booth, but when I recorded it was me, Nora and Daveed, Halle was there too. I thought it was a rehearsal but that was actually the recording but because everyone was there, I did my one hundred, and thankfully I did that!"

Julia Roberts as Isabel & Jacob Tremblay as Auggie in Wonder

Will you be watching The Little Mermaid’s live-action movie? Early reactions to the film are already in, with one person tweeting: "#TheLittleMermaid is #Disney's best live-action adaptation, in that it succeeds not just as nostalgia but as an often stunning film in its own right. Not PERFECT, but it's got the Disney magic! And should definitely be seen on the big screen."

Another person added: "As someone who has never loved #TheLittleMermaid, the new version w/ @HalleBailey makes small but significant changes that give you a new appreciation for Ariel & her journey. Still the same heart. Just new eyes. For her. For Eric. For the romance. And it works."

See more photos from the premiere here

The Little Mermaid is Halle Bailey's first major role — The Little Mermaid is Halle's first major role

Simone Ashley exuded effortlessness in a pale peach sheer gown with a shredded hem

Nife went all out in a full-blown mermaid ensemble

Stefflon Don brought the drama in a green frothy showstopper

Janette and Aljaz attending the premiere — Janette and Aljaz looked totally smitten

Kajsa Mohammar wore a radiant pink one-shoulder gown

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