Wait for Dark by Kiersten Modglin

They want an ideal life.
She’s the only thing standing in their way.

The Ashleys are determined to build a future detached from the issues in their pasts, and it seems to be working.
They’re happily married.
In love.
Established in their dream careers.
Closer than ever to being debt-free.

But when a mysterious opportunity arrives with an offer they can’t refuse, everything changes.

Soon, they meet her.
She’s rich.
Powerful.
Single-minded in her goals.
She is not used to being told no.

Worst of all, she knows about the dirty deeds they’ve done in the dark…

If they don’t do exactly what she wants, the ramifications of their secrets being exposed are endless. In a battle of wits against a woman who knows too much, the Ashleys find themselves with an impossible choice to make.

Whom do you trust when the only person who can save you is the one who might bring you down?