AN: Please find Allegretto from Palladio by Karl Jenkins and listen to it while reading as this is the piece I envisage Sherlock playing. Just an idea and with light down low...
Only after months of insignificant cases, of bullets holes in the walls, chemical explosions and annoying Mycroft comes to no avail. Only when there is no other possible outlet for the the boredom trapped in Sherlock's skull, pounding his brain constantly, will he dress carefully in the suit kept in the back of the wardrobe, polish his violin before sending a single text. Then he will walk – not sprint, amble or take a cab on this rare occasion- with single minded determination towards the Barbican center.
When the nights' first violinist receives the text he curses quietly, but reluctantly shows the text to the PA who then telephones the Director (who leaves her phone on constantly for emergencies like this) explaining, a little bewildered for it's only her fifth month, the situation. The Director sighs before letting the PA know that the lighting levels would need to be low tonight's performance. The first violinist, a little disappointed, goes home and has a quiet night in; he had been looking forward to the night's program. His girlfriend however is pleased with this unexpected night together.
When John returns to the flat after a long day at the clinic, he finds a single ticket to the evening show with the words "Go please." in Sherlock's distinctive script. Accustomed to strange events like this he obeys the request with only the minimum of required grumbling (he has to keep up some standards).
The music echos around the the concert hall; the restless beat exhilarating but strangely calming. None of the audience observes that the first violinist's chair is filled with a person who's face or name definitely aren't featured in the program - except perhaps one. John wisely doesn't comment about Sherlock's shaking fingers when he returns home or the fact the Sherlock barely makes it to the sofa before the weeks of sleep deprivation catch up with him. Or about the smile on Sherlock's face as he at last drifts off to sleep.