It is a TV programme renowned for knowledge of the esoteric.

But surely few contenders in Mastermind’s famous black chair can have made the leap undertaken by Scot John Savage: from the history of Celtic FC, to Nazi Germany (1939-45).

Or, to quote the sales executive: “I went from Hail Hail to Heil Heil.”

When the qualifying heat was shown last month, Mr Savage, 52, of Polmont, Falkirk, collected 11 points out of 14 answering questions on his club, in what the first time anyone had picked Celtic as a specialist Mastermind subject. He added a further 14 general knowledge points.

Mr Savage, who is married to Lynne, and is dad to Andrew, 14, appears in the BBC show's semi-final on Friday March 29, and has given HeraldScotland an exclusive behind-the-scenes insight.

He writes: "The semi-final was recorded in Salford in October last year and due to it falling on the same day as Manchester Utd playing a home European tie the same evening, the prices of the hotels increased accordingly.

"We decided we would go to Liverpool to stay for a couple of days then travel to Salford on the day of the heat and stay the night in the hotel at the studios. The BBC pay for one night accommodation.

"We reached Salford at lunchtime, checked into the hotel and I changed into my 'stage clothes' prior to entering the studio. We knew what to expect this time so a lot of the novelty was gone, but it was still a good feeling to go up in the lift to the hospitality area.

"You are asked to arrive about two hours before recording as I suppose this helps the contenders (never contestants) relax and prepare accordingly. There were other contenders in the Green Room, as several heats are recorded back to back, but everyone tends to keep to their own guest group.

"Food and drink (no alcohol) are provided and there are several members of the production team on hand who go out of their way to make everyone welcome and relaxed, and nothing is too much trouble for them.

"After an hour or so the contenders are taken aside, told the order of seating for the show and a brief rundown on what we say during our introduction and a reminder of the rules.

"The tension starts to build and while some contenders are upbeat (me), some choose to sit by themselves and check over last minute notes. I didn't do this as I felt I had taken on all the information I could and preferred to go on 'cold'.

"A short time after this we were taken back down to the dressing rooms and the 'miracle workers' (or make-up as they're known).

"On arrival downstairs your dress is checked for suitability (no logos, thin stripes etc). Make-up is then applied (not a great deal, despite what some of my friends said) and your personal microphone fitted.

"After a short time we were taken into the studios and introduced while walking to our seating by Ted Robbins, the warm-up act. Last checks are made on make-up, you're reminded of the rules etc, then finally there is a brief period where the contenders have to sit perfectly still while various shots are taken of them for the close-ups shown at the start of the programme.

"The music starts and you're on…the semi final consists of five contenders, four heat winners and a best runner-up, and the times are changed: 1.5 minutes for your specialist subject (mine was Nazi Germany 1933-45), and two minutes for general knowledge.

"Obviously, I can't reveal the result, but I will say the heat was very exciting and I hope the viewers enjoy it."