When Matthew McConaughey’s son Levi scored a role in his first film alongside his dad in the new movie “The Lost Bus,” the veteran actor made sure to let him know the ropes on set.

McConaughey, 55, spoke to Jenna Bush Hager and Cardi B on TODAY on Sept. 16 about showing his 17-year-old son some tough love ahead of his role in the Apple TV+ film, which comes out on Oct. 3.

Levi stars as Shaun McKay, the son of McConaughey’s character, Kevin McKay, a bus driver who made a harrowing rescue of a teacher and a group of 22 children during the deadly Camp Fire in California in 2018.

“I had to tell him, this ain’t no bs-ing around,” McConaughey said. “It’s play, but the preparation, it’s work, it’s a rodeo. This is not about showing up with attitude. So I was somewhat hard on him early and continued to be, just to teach him as much as I can, but once he got on set, this is great, you’ll know this moment.

“That day when he went to set, he wasn’t looking at me for any sort of approval,” he continued. “And I was happy, as a father, to go, ‘When you show up, you better own it. Don’t be getting there auditioning, saying, ‘Can I ask permission or have take two,’ … You got one take, let’s go.’ And so he owned it that day and didn’t look to me for any supervision, didn’t look to me for any approval, and I sat back and just kind of went (claps hands).”

Levi, who is one of McConaughey’s three children with wife Camila Alves, immediately expressed interest in the part.

“I pitch the story of any movie I’m going to do to my family as I always do, and then I got to the part about having a son, and my son Levi goes, ‘Well how old is the son?'” McConaughey said. “I go, ‘Well he’s about your age.’ He goes, ‘Can I read for it?’ I was like, ‘Huh.’ I want to hear him work for it. He came and badgered me again and again and again, and finally I said, ‘OK, yeah you can read for it.’”

McConaughey helped him prep for an audition for the film, which was directed by Paul Greengrass of “Captain Phillips” and the “Bourne” movies fame.

“It hadn’t been cast yet,” he said. “I talked to him about acting, we worked on the scene, put him on camera. He was good. I sent it to the casting director. I said, ‘I think this might be good enough for a callback.’ Casting director wrote back and said, ‘I think it might be good enough to send straight to the director.’”

The “Dallas Buyers Club” star was on board, with one stipulation.

“I said, ‘Well if you do that, please pull his last name off of it,'” McConaughey said. “If he gets it, I don’t want him thinking it might’ve had to do with his last name, and if he doesn’t, either way.”

“So she pulled his last name off, the director saw it and said, ‘That’s the kid.’ And she goes, ‘Well, that’s actually Matthew’s son,’ and he goes, ‘Even better.'”

America Ferrera, who also stars in “The Long Bus,” spoke on Sept. 11 on TODAY about working with Levi on the set. She said he worked with the camera department after wrapping his scenes.

“I thought, ‘Why does that kid look so familiar?’” she said. “Matthew’s like, ‘That’s my son.’ And I was like, ‘Because he has your face. That’s why.’ But he was the camera intern. He was so great.”

Levi isn’t the only McConaughey family member in the Apple TV+ movie. McConaughey’s mother, Kay McConaughey, 93, plays Sherry McKay, the disabled mother of Matthew’s character.

“We’re halfway through production and (Greengrass) goes, ‘I got to cast the role of the mother, how about your mom?'” McConaughey said. “I go, ‘Mom send me a tape, a minute that says why you love being a mom,’ and my mom sent an eight-minute tape because she was being a mom. He looked at it and goes, ‘That’s her.’ And all of a sudden, there we are with my mom and my son in a scene.”

McConaughey, who is appearing in his first movie in six years, cherished the time being able to work with his son and mother on the film.

“And that’s something that’s going to get nothing but cooler with time to look back on it,” he said.