Who is GMac: Meet most feared man on The Block 2025

He's the man you don't want to mess with but you'll certainly want his approval on The Block, so who exactly is GMac, and what does he do on site?

GMac a.k.a 'The Mac Daddy' is the strict rule enforcer and Site Supervisor on The Block 2025. Three weeks in and House 5's Mat is still "terrified" of him...

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With big plans for Main Ensuite Week, nothing can go ahead without sign-off from GMac, especially waterproofing.

"I'm so scared of him!" Mat confessed.

With their waterproofing approved, Robby jumped in for a "celebratory selfie". Mat's jaw dropped as Robby's gesture was hilarious rejected.

"He's an intimidating man, I'm just terrified," Mat reacted.

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Robby made a vow: "You know what, when the show's over we're going to have a nice photo with him, the three of us, and he's going to smile and you're going to be smiling."

Mat also confessed that whenever GMac enters the room, the theme song of a famous villain comes to mind.

Listen to his hilarious song below:

Who is GMac on The Block 2025?

Nothing gets past GMac and his all-important sign-off.

In the words of House 4's Sonny and Alicia: "He's the maker or breaker, the man above Foreman Dan."

In the words of House 5's Mat: "G Daddy, he terrifies me."

As GMac cracked the whip during Kids Bedroom Week, Mat took creative liberties and bestowed a multitude of nicknames on him: G-Flip, G-Wagon, G-Dog, G-Daddy and allegedly, G-String.

"He's such a lovely guy but when he comes on site he means business," Mat described GMac's dominating presence.

"I find him terrifying."

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GMac cracks down on waterproofing

As Guest Bathroom Week kicked off, this year's Blockheads had one more hurdle before waterproofing could officially start.

That hurdle was GMac's inspection. Without GMac's sign off, no waterproofing would be allowed.

"I'm so scared of him, he reminds me a little bit of Professor Snape," Mat drew a comparison between the foreman and the Harry Potter star.

"It's because he has his phone with all of his checklist and it's terrifying and he moves really slowly when he's judging your room," said Mat. "The thing is, if you haven't done something right he will eat you alive."

"If he looks at your wall and it's not perfect, your wall is coming down."

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If there's one thing you don't want to do, that's waste GMac's time.

"GMac is a beautiful man... he never smiles," spilled House 3's Taz.

He also apparently "doesn't do hugs". But one thing GMac does appreciate is the willingness to learn and good ol' hard work.

Show up and take initiative and you just might get a smile and handshake from the man himself.

What is GMac's experience on The Block?

GMac is also the "head know-it-all" of Nine in Six, the builders overseeing all five houses on The Block this year.

A force of nature, fans may remember GMac from The Block's 20th season on Phillip Island. Anything Foreman Dan and GMac says, it goes.

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"You don't want to p--s him off, because then you're in trouble," warned Sonny with a smile.

GMac also certainly made his mark during the 2022 Gisborne season.

As winners Omar and Oz were dealt the harsh truth to "forget about winning" but rather do the job right.

Turns out that was some pretty solid advice, as the stars walked away winners of The Block 2022 in the end!

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The Block airs Sundays at 7pm and continues Monday to Wednesday at 7:30pm and Sunday at 7:00pm on Channel 9 and 9Now.

Stream every episode ever of The Block for free on 9Now.

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