Now in charge of a schoolhouse occupied by the old Rochdale kids, Grantly has more responsibility than ever on his hands - and viewers won't be surprised to hear that his patience is tested on more than one occasion as he settles into the new lifestyle!
Digital Spy recently chatted to Philip Martin Brown, who plays Grantly, to hear his take on Waterloo Road's relaunch and what's ahead in series eight.
How well have you and the rest of the cast settled into Scotland?
"We've settled in remarkably quickly. We didn't think that we would, but we have. I've been very lucky with my career, as I've travelled quite a lot around the world, and I can honestly say that Scotland has got the friendliest people of any nation that I've visited. That's really helped.
"For the show itself, the situation in terms of location has also been great. We've got the River Clyde as a backdrop to the school, and that opens up new possibilities for the writers and directors. The new school is also much bigger, which makes filming easier."
Do you think Waterloo Road's fans will accept this change to the show?
"Yes, because even though it's a different school, the interior of it looks remarkably similar to the old one. The designers have been very clever when creating this school, as they've kept it as similar as possible to the one we left behind.
"There will be more Scottish accents in the show, but I think that's something that the viewers will take to very quickly. I expect that after the first few episodes, people will be completely used to the fact that it's now in Scotland."
Was it sad to say goodbye to Rochdale after seven series?
"Yeah, it was sad. In fact, I was surprised at how sad I was, but it was because I'd made friends in Manchester - outside of Waterloo Road and the filming business, so I felt really at home there.
"But Glasgow is such a friendly place and it's great to have the car here. My wife has just been up to visit, so we went off to the Isle of Skye and up to the west coast of Scotland, which is just beautiful."
Did it take much consideration as to whether you wanted to move to Scotland with the show?
"Not at all, as I love Waterloo Road and I love playing Grantly. It really was a no-brainer for me."
In this series, Grantly and his fiancée Maggie are running the boarding house for the kids from Rochdale. How does Grantly cope with that?
"Well, it's a bit like having a red hot poker shoved up his backside! He hates it. He's got the kids during the day and he doesn't like that very much, and then when he's finished and has put his pen down in the classroom, he goes back home and there they are again!
"Grantly has got to spend time with the kids 24/7 and he can't bear it. But Maggie loves it, so he puts up with it for her sake - and the money's sake!"
Are there any particular pupils at the house who cause problems for Grantly?
"All of them, in their own way! In one way or another, each one of them causes stress and aggravation."
There's obviously some new teachers joining the show in the new series. How well does Grantly get along with his new colleagues?
"Not very well at first. But then he finds out that one of them likes a drink, so he forms a bond immediately there! There's also a lady called Audrey, who he gets off to rather a shaky start with because she's in many ways similar to him, so there's a clash of personalities. Those two don't get on brilliantly, but as the series progresses, they do warm to each other.
"There'll also be a new secretary, who Grantly thinks is just as stupid as the last one! But then again, he thinks everyone's stupid - other than himself and possibly Maggie!"
We've heard that there's a bit of a feud between Waterloo Road and another local school, Havelock. Does Grantly play any part in that?
"Yes he does, because in any way they can, these kids from Havelock High attack Waterloo Road - be it the school or the schoolhouse. Nothing is sacred for these kids, and so Grantly gets in the firing line here, there and everywhere!"
The final ten episodes of the last series were very busy for you with the Fleur storyline. Are you equally as busy in the new series?
"With the first ten episodes, there are a couple of episodes in which I'm very busy. But as with any ensemble show, you take turns - everyone has their bite at the cherry, then takes a back seat, and so on.
"That ensures everyone gets their fair share. However, you'll see in episodes 20 to 30, there is going to be a very big storyline for Grantly."
With the show now on its eighth series, did you ever imagine that Waterloo Road would have such long-lasting appeal?
"Not at all - I thought there was probably two series in it. I never had any idea that it would go on for so long. I think what happens is that families sit down and watch it together, which is lovely, because there are very few shows like that now.
"Even if a child or teenager loses interest in the show, then there's always an 8-year-old who is just getting interested in it. So where one drops out, another one takes over."
Have any of Grantly's storylines really stood out as your favourites?
"Yes, there was a girl with Asperger's syndrome called Karla back in series three, who Grantly really didn't like. I was the villain of the piece in that story and a bit of a monster, because I had a real go at her. I enjoyed that storyline.
"There's also Grantly's wig - I still miss it! I had a toupee that I thought was the bee's knees, even though it moved all the time and looked ridiculous. All of the staff were trying not to giggle, and in the end, it was taken by a sniffer dog who ran away with it!
"There was also the Fleur storyline last series. So those are the ones that particularly stand out thus far. There's also something that happens in episode seven of this next series…"
Were you sad to see Chelsee Healey leave the show while filming this series?
"Yes, I first met Chelsee when she was a student and then she left because she was too old to stay in the show. I was thrilled when she later came back as a secretary - she was great fun to be around and made everyone laugh. She's sorely missed, but she's gone on to great success - it was amazing to see her on Strictly Come Dancing."
Some fans may not know that you've done some teaching in real life. Have you specialised in a particular subject?
"Well, I learned to teach drama and English, so it's art imitating life in a way, as I'm an English teacher in Waterloo Road! It's been very handy, because I've been able to bring things to the show that I've noticed in real classrooms. Grantly is an amalgam of a teacher who taught me at school and people that I've met over the years in staff rooms, because there's always someone like Grantly!"
Is it strange for kids to watch you on television and then see you in the classroom the next day?
"Well, I haven't been in a classroom for about four years, but I only ever go to one school, which is a comprehensive close to where I live. They were quite used to seeing me on the telly and then in the classroom the next day.
"But in the very first year I was doing it, I was in a show called Band of Gold, and I was playing a villain who was caught by the police in bed with a rent boy. The next day, I walked into a classroom, so you can imagine the shouts and the whistles!"
We asked for questions on Twitter, and one fan wanted to know whether you'd like Steph Haydock to make a shock return for a reunion with Grantly…
"I would always like Steph Haydock to make a shock return, yeah! I've been really, really lucky with the females that I've played against on Waterloo Road. I've been paired with Denise Welch, Elizabeth Berrington, Lorraine Cheshire and now the lovely Melanie Hill. I couldn't have asked for better."
How close are you all as a cast on the show? Is there anyone in particular you'd spend time with outside of work?
"I think it's easier to say that there is no-one on set that I wouldn't spend time with outside of work! I've been really lucky - Waterloo Road has possibly been my favourite job, because everyone gets on so well and there is a social life involved. We all get on well and there's no rotten apple in the barrel - it's brilliant."
> Read the latest 'Waterloo Road' spoilers and news
Waterloo Road launches its new series on Thursday, August 23 at 8pm on BBC One.