Bridget had seen pictures of Siobhan with her husband Andrew, and she knew what her twin sister was like, so she knew exactly the kind of man Andrew Martin was.

The photos had been the very definition of bloodless and fussy, with Siobhan and Andrew stiffly posed next to one another, her in some sleek, emotionless designer gown and him in a suit that made him look like…a suit. He seemed like the kind of businessman whom Bridget had had a lot of experience with in her line of work: he ran his marriage like he ran his companies, with exacting schedules and a low tolerance for mistakes, and he hired outside contractors to handle the dirty, exhausting, messy stuff.

An outside contractor much like Bridget herself.

She had wondered how Siobhan tolerated being married to one of those men, the kind of men who went on business trips and even before they'd checked into their company-paid-for hotel suites had booked a woman through the recommended call girl service.

But Siobhan had always dated that sort of man. When Siobhan was in college and Bridget was "working" sometimes — not often, but sometimes — the two of them spoke on the phone. Siobhan was always dating a guy who was "pre-law, with a definite intention of working on corporate litigation" or who came from "a very good family" (which always meant extremely wealthy, with an expectation of starting off in top management). Whenever Siobhan and one of these prime specimens didn't work out, it was because their "expectations had diverged."

Once, and only once, Siobhan had admitted it was because the guy had left her for a woman who'd put out more than once a week at the scheduled time.

Siobhan had always dated that sort of man, and Bridget had always been hired by that sort of man. Bridget knew perfectly well what her brother-in-law would be like when she met him face-to-face. She knew how to handle him.

And then she met Andrew and discovered exactly how wrong she was.

The sound of four-inch-heels clacked on the wooden floors of Siobhan's co-op as Bridget walked through it. Siobhan's shoes, Siobhan's white designer clothes ensemble, Siobhan's diamond earrings. So far the deception was working. So far, every single person who'd seen her — the housekeeper at Siobhan's little seaside retreat, the car driver tasked with escorting Siobhan through Manhattan, the doorman of this magnificent Upper East Side co-op building — had greeted her as Mrs. Martin.

It had seemed like such a good idea at the time. Bridget was scared and alone and on the run and no one in New York City knew she existed. Of course not: Siobhan wouldn't want anyone to know that there was anyone who approached her in fabulousness, certainly not a sister who'd tumbled down the staircase of life from high-priced call girl to stripper with a prescription meds problem. Better to be an only child than that, certainly.

Now Siobhan was gone, vanished, disappeared. Bridget didn't know where her sister was, but right now Siobhan wasn't here and Bridget needed to hide. Here.

When Bridget had guided the boat back to the harbor in the Hamptons, she had thought, I can hide in plain sight, right here, as Siobhan. Just for a while. Just for a few days.

Then the housekeeper had reminded her that the contractors were starting work on the beach house come Monday morning and the house would be nigh uninhabitable for a month. The car driver had shown up, ready to take her back to the Upper East Side.

Bridget had put her wrap-around sunnies on and gotten in the back of the silver car.

The driver took her to the building and the doorman let her in. The fob on Siobhan's keyring had unlocked the elevator, taking her directly to her floor. And that apartment! Unbelievable that her own sister actually lived in such a place. The size of it — anywhere, let alone in Manhattan, that was a huge apartment. The living room furniture in white — the only people who could afford to have a living room all in white were the ones who didn't mind paying for reupholstery when a drop of white wine stained the chandeliers and those beautiful, noisy hardwood floors.

The giant portrait of Siobhan smack at the entrance to the apartment was a little much. Honestly, what had possessed her sister to put such a thing up so prominently? Or to put it up at all, for that matter?

Siobhan's life was fabulous. Bridget would only borrow it for a while. Until she was safe. Until both of them were safe.

She went to Siobhan's closet to see what kind of clothes her sister wore. Everything looked so streamlined and uncomfortable. The sexy ice queen vibe. Bridget ran her hands over the fabrics and looked at the cabinets custom-built to hold Siobhan's shoe collection, which was organized by color, heel size, and designer.

She didn't hear the door to the co-op open until she heard a man's voice say, "Siobhan! I'm home!"

She turned, and there was Andrew, home from the airport, wheeling his suitcase behind him.

Bridget had known a lot of men, known them in all sorts of ways. She gotten pretty good at sizing them up right away. Andrew Martin was no idiot. When businessmen hired Bridget to be their "weekend girlfriend" and complained about the Master of the Universe who was running their company, the kind of man they were describing was Andrew Martin.

Andrew Martin, Master of the Universe. He probably had it on his business cards.

Two things immediately came to Bridget's mind as Siobhan's husband walked down the hallway to her:

1) He wasn't supposed to be here, in New York, in this apartment. Hadn't Siobhan said he was going to be on a business trip for a while? That was why the sisters could stay in the Hamptons for a while and no one would bother them? Bridget couldn't fake being Siobhan in front of her husband! She didn't want to fake being Siobhan in the most intimate relationship two people could have!

2) My God, that was her sister's husband?

That wasn't just some guy Siobhan was married to. That wasn't the bored, stiff number cruncher from the photos. That was a man.

Suddenly Bridget's plan to impersonate her sister seemed completely inane. There was no way this man wasn't going to know right away that she wasn't Siobhan.

Her entire plan suddenly seemed insane. The second she opened her mouth this Master of the Universe would know he had an impostor in his home and he would have her arrested.

She either had to throw herself on his mercy right now and try to explain everything — including his wife disappearing in the middle of Napeague Bay when no one else was around and how Bridget had started impersonating her — or she had to go all in on pretending to be her sister.

Asking for mercy meant being sent back to FBI custody in Wyoming. Back to her death. Wasn't that why she ran? She only needed to be Siobhan for a while. How hard could it be?

This was Siobhan's house, Siobhan's husband, Siobhan's rightful place in the universe. Bridget just had to act like it.

So she greeted Andrew with a flirtatious "Hi" and kissed him.

Which was a terrible, terrible mistake.

Because his lips were soft and ever so inviting.

And also because the look on his face made it clear that he and Siobhan didn't kiss, ever.

If I've gotten this wrong, she thought, what on Earth am I going to get wrong about their relationship?