The Invisible Woman

My name is Elinor Gilbert. And I am the Invisible Woman.
Elinor Gilbert was once a young woman with a thriving career at the FBI.
Now, decades past solving crimes with the bureau, she is personally and professionally forgettable.
Which is exactly what her former FBI boss needs. He disguises Elinor as a middle-aged nanny, and casts her as an agent on the inside of his investigation into a New York art dealer suspected of ties to organised crime.
But as Elinor pushes toward the truth, her superpower - anonymity - risks doubling as a fatal flaw.