Andrea Riseborough (Charlotte) and Jaimi Barbakoff (Heather) in A Short History of Helen of Troy Janine Jansen's reputation amongst the new generation of violinists stands deservedly high - yet it was hard to approach this concert without misgivings.
The kitschy marketing, the use of Vivaldi's over-familiar Four Seasons as a star-vehicle... there were troubling hints that we were about to witness a sublimely talented player making a particularly depressing career-move.
Wrong on all counts. The "Jansen Ensemble", far from being a hired backing-group - la Kennedy, is a septet of performers with whom Jansen clearly enjoys a more than merely professional musical relationship.
The sense they conveyed of shared pleasure in the music made this a rare instance of a celebrity soloist truly playing as first amongst equals.
In Bach's D minor Concerto (BWV1052) - as throughout the programme - Jansen played with a glowing but infinitely nuanced tone, here weaving in and out of the texture like a golden thread.
Against the Ensemble's vibratofree articulation, it should have sounded anachronistic. Instead, it made wonderfully lucid sense of Bach's knotty passagework.
If the finale of the E major Concerto (BWV1042) didn't quite dance, that was only because the group's entire conception of the concerto was lyrical - with viola player Maxim Rysanov and bassist Stacey Watton amply matching their leader in song.
And the Vivaldi was equally convincing. From the freshly-phrased opening ritornello of La Primavera, and Jansen's first solo birdcalls, this was a reading that brilliantly restored the colour and imaginative richness of these hackneyed concertos.
Played with unanimity and startling energy, and touched-up with shivers of ponticello and snapping pizzicati, they emerged as four vivid, Breughel-like landscapes. With the whole Ensemble beaming delightedly at the final chord, it was hard to imagine modern-instrument Vivaldi done better. Glorious entertainment.