and see she's logged on to h.com (which you didn't know she knew about), under a male screenname. Startled, she tries to pretend nothing happened, says she has to go do laundry, turns off the monitor and goes out of the room. In your curiosity, you turn it back on and check her private messages. There you discover a romantic exchange between your wife posing as a male, and a female member of h.com. They even scheduled a date, and it is tonight. As you finish reading this, you hear steps and quickly turn everything off.

Do you go spy on the date? Do you hire a private investigator? Do you confront your wife?

I would spy on the date and try to take photos and maybe even record video. Regardless of how it plays out, it can't hurt to have evidence.

For further discussion:

Is this discovery worse, the same, or better compared to if the wife was doing this under a female screenname?

It is better because at the very least it is interesting how it will play out - how will she handle the transition from a pretend-male to a real-life-female when they finally meet?

Au contraire, that deception might cause the "date" to end quickly; if she had been under a female name there is a much greater probability of the date going on for a while and potentially getting interesting.

Au contraire, perhaps she is aware of something you're not. Like that the person on the other end, hiding under a female name, is actually a male. Then things will not only get interesting, they might get ugly.

ETA: And if your wife is _not_ aware of it, then it might be over even quicker.