He's an actor, a comedian, a TV game show host, a Classic FM presenter - and a classical baritone. But what's Alexander's guilty pleasure?
When Catherine's not broadcasting she loves to watch Corrie - and Kenneth Williams conducting!
If you could sit down and have a coffee with one great composer, who would it be?
Henry Purcell. I'd love to spend some time with such a great songwriter. But, NO COFFEE! He preferred drinking chocolate - a mouldy batch may have led to his death - so we'd go to one of his favourite pubs near Westminster Abbey for a beer!
Favourite ever interviewee or guest?
Murray Perahia - a privileged hour of insights delivered with modesty and humour by my piano hero.
Who would be your four perfect dinner party guests?
Lord Nelson and his mistress, Lady Hamilton (for sexual chemistry, naval anecdotes and singing); her husband, Sir William Hamilton (art connoisseur); and Josef Haydn (to play for Lady Hamilton after dinner).
What’s your guilty pleasure?
Not a shred of guilt - Coronation Street . Great popular drama which makes great use of music, especially the classical tracks in Roy's Rolls.
Most memorable concert you attended?
Two unforgettable concerts, both in 1996: pianist Radu Lupu playing Schubert in Salzburg and Barry Manilow in concert in Las Vegas. Yes really, Manilow is a true musician's musician.
Which superpower would you like to have?
I'd like to be the Cold-Curing Fairy, visiting ailing singers and zapping those germs.
What's your favourite snack when you're feeling a bit peckish in the Classic FM studio?
A can of ginger beer from the studio cafe.
All-time favourite piece of music?
Bach's B-minor Mass.
All-time favourite book?
Noel Streatfield's Ballet Shoes. "Never forget that an actress can learn until her last hour."
All-time favourite film?
Raising the Wind (1961) - a sort of 'Carry On Up the Music College'. Worth it for Kenneth Williams conducting the William Tell overture alone.