A doctor or a hospital consultant. A career in the police or the law. All may well feature in the aspirations of graduates fresh out of college. But Sarah Travis’s career went in a much more unusual direction: she became a musical arranger.

“I had a very inspiring teacher called David Thomas at my secondary school, in Midsomer Norton, Somerset. He played by ear, and he encouraged me: when I was 12 or 13 I had started taking pop songs off the radio, but not playing from any music. Thankfully, he said I must go on to music college.

“After that, I had no idea what I was going to do. I became an accompanist first of all, and early on played for Fascinating Aida, Dillie Keane’s one-woman shows, Julian Clary, Lily Savage — I loved that comedy-cabaret sort of circuit. I did a bit of musical directing too. Then I met [theatre director] John Doyle, and we did Pal Joey together in York in 1993.

“I’d not really done a lot of arranging up until then — although sometimes I’d had to write chord sheets for bands, or some bass parts for a small combo, or whatever. It was very scary, because suddenly I had a cast of 15, and there was some big band scoring in Pal Joey. So I shared the arrangements with Catherine James, who has also worked a lot here at the Watermill.”

Sarah Travis, pictured below, and I were talking at the Watermill Theatre, just outside Newbury. The tiny Watermill has punched well above its weight for many years, transferring its home-grown productions of Shakespeare and musicals to the West End, and touring them both in this country and across the world.

First under the direction of John Doyle, and more recently under Strictly Come Dancing’s Craig Revel Horwood, the Watermill has developed a tradition of musicals performed by multi-skilled casts — you must be able to sing, dance, act, and play at least one instrument to a professional standard.

“I find it very humbling when I hear and watch people doing all those things at once,” Sarah told me. “Robin Colyer, the bass player, for example, does a walking bass line, he tap dances, and he sings, all simultaneously. That really is patting your head and rubbing your tummy at the same time. The bar is being pushed higher with every show we do.”

Sarah Travis has so far been arranger and musical director on no fewer than 12 Watermill musicals.

When we met, she was just beginning rehearsals on a revival of Hot Mikado, first staged three years ago. But this time around many of the actors are new to the production, and play different instruments. So adjustments are needed.

“I’ll tinker away. That’s the bit I like, because I’m using my ears. What else have I got? My ears are everything.”

But what happens if Sarah hears, say, a superb sax player at an audition for a Watermill musical, but Craig Revel Horwood decides he or she can’t dance for toffee?

“A lot of bartering goes on, of course! I have a wish list of the line-up I want. When we first did Hot Mikado, I knew I wanted a fat brass section, a wind section, and some saxes. I knew it was going to be BIG. We might weight someone more musically if it’s an important role, or more from the dance point of view if Craig says a certain character has to be a tap dancer, for instance.”

In 2006, Sarah Travis won the stage equivalent of an Oscar — a Best Orchestrations Tony award for Sweeney Todd, a Broadway production that began life at the Watermill.

Her career had indeed come a long way from her early days, pounding the piano for the Chipping Norton panto. And yet, Sarah is not at all the sort of person who has become too grand to revisit her past — and her love of the Chippy panto is plainly alive and well.

“I have very fond memories of Chipping Norton, particularly of Tamara Malcolm. I learnt so much there — I was very green. It was similar to here, everybody working really hard, and you get this exciting product at the end. But winning the Tony was just one of those moments in time, it was a bit surreal.”

  • Hot Mikado is at the Oxford Playhouse from October 13 to 17. Tickets 01865 305305 or online at oxfordplayhouse.com