In which your humble correspondent is appalled and distressed

Dear Mr. Mann,

Whilst I understand both your modern need to be inclusive and your desire to keep your readers guessing, the inestimable Mr. S. Holmes would never so mangle the Queen's English as to use a plural pronoun with singular verbs and to do so for several paragraphs.  Frankly, I am shocked at this lapse in an otherwise excellent series.  For shame, sir, for shame.

Very Truly Yours,

Jammies

P.S.  Torturing the language to make it gender-neutral only makes it very clear to the reader that the villain is, in fact, the female character.

Yours, etc.