The Invisible Spy begins with a playful account of how an unknown author's identity might be constructed by curious readers:

If we accept as truth an anecdote in the earliest biographical account, Haywood's identity was a mystery she took care to preserve. In David Erskine Baker's The Companion to the play-house (1764), we read that ‘she laid a solemn Injunction on a particular Person, who was well acquainted with [her History], not to communicate to any one the least circumstance relating to her’. That injunction was evidently obeyed. Despite her prolific career, Haywood left little trace on the historical record. We know only that by 1715 the woman who later informed a potential patron that her maiden name was Fowler, appeared as Eliza Haywood in the cast list for the Smock Alley theatre in Dublin. The identity of her husband is unknown, but we glean from her letters that the marriage was ‘unfortunate’, and that Mr. Haywood died suddenly, around the same time as her father. She turned to writing to support herself and two children, the eldest of them being ‘not more than 7’ in 1729. Haywood reveals little about herself in her work, but then self-revelation or confession was not generally the early eighteenth century mode.