Philip Martin Brown reveals how his Waterloo Road character Grantly tackles his most challenging storyline yet…

So how do we find out what is behind wife Fleur’s strange behaviour?
“Fleur arrives at the school in a very dishevelled state. It’s the middle of winter and she has no shoes or socks on. Ruby finds her and it finally comes out that Fleur has Alzheimer’s.”

Is it strange that Ruby is the one he confides in?
“Yes. Beforehand they didn’t get on particularly well, but after seeing Fleur she becomes a real friend. Ruby helps to keep Grantly’s secret and she becomes his confidante.”

Does he get outside help?
“Grantly can’t deal with it on his own, but to him it’s family business and other people don’t need to know. He thought that the problem was containable, but once she arrives at the school he has no idea what to do.”

How did you find tackling this subject?
“I realised that it wasn’t something that I could take lightly because of the amount of people in the country who suffer with this terrible disease, so I did a bit of research. I went to a day care centre for people with Alzheimer’s, so I was aware of the importance of trying to give the storyline as much truth as possible. There were moments that it was distressing to film though, because Lorraine Cheshire is so good at playing Fleur.”

But you still love playing Grantly?
“He’s a joy to play – he’s an amalgamation of different teachers I’ve met. Viewers like him because he says things that a lot of people think but can’t say in the PC world in which we live.”

And you teach yourself?
“Yes. I work as a supply teacher at my local comprehensive. I have a different teaching style to Grantly – I hope I’m more accessible! The pupils are used to me now, but when I was in Band of Gold, I had to do a scene in bed with a rent boy. The following day, after it had been broadcast, I went to the school and you wouldn’t believe the shouts and the jeers I got! It’s all good fun!”

*Waterloo Road screens at 8pm on Wednesday evenings on BBC1