The star posted a topless picture to his account, wowing fans with his ripped body!
He captioned the post: "#tbt to when I listened to everything @zacefron told me, lol."
#tbt to when I listened to everything @zacefron told me, lol."
Fans rushed to comment.
One wrote: "That's ridiculous. Are you a cyborg?!" with a heart-eyed emoji.
A second commented: "Damn. Hard work truly pays off."
"You look incredible. A lot of hard work going into that!" added a third. Others commented: "Fit," and "Wow."
Someone else requested his return to EastEnders: "If Peter Beale comes back to the Square one day then it needs to be you playing him," they said.
Fans of EastEnders will remember Thomas played Ian Beale's son from 2006 till 2010.
He left in 2010 to go and stay with his twin sister Lucy, who had gone to live in Devon with their grandmother.
When the character returned in 2013 he was played by Ben Hardy.
Since leaving EastEnders, Thomas has had TV and film appearances.
In 2013, he had a role in Simon Pegg and Nick Frost's third and final installment of the Three Flavours Cornetto Trilogy, The World's End.
Thomas played a young Gary King. Adult Gary was played by Simon Pegg.
The film was directed by Shaun of the Dead and Hot Fuzz director Edgar Wright.
The following year, Thomas appeared in an episode of Casualty.
In 2016, Thomas starred in A Cinderella Story: If the Shoe Fits alongside Disney Descendants actress Sofia Carson.
It now seems like Thomas is focusing on his music as he's posted some clips of him playing guitar and singing on his Instagram page.
The former child actors were at a wedding and posed for a photograph at the celebrations.
While Thomas looked dapper in a dark suit and tie, Madeline looked like a green goddess in her emerald frock.
Madeline captioned the post: "Peter and Lauren bump into each other at a wedding 8 years later."
Do you think Thomas looks different since his soap days? Leave us a comment on our Facebook page @EntertainmentDailyFix and let us know!