For Rebecca Miller, marriage is an adventure. When you're Mrs. Daniel Day-Lewis, "honey" is a man who eats nothing but prison slop for days, skins animals himself and insists on being spoon-fed at restaurants while confined to a wheelchair -- all to prepare for roles.

In the epic Gangs of New York, he lost himself so thoroughly in his Oscar-nominated role as Bill "The Butcher" Cutting, "he could have butchered a pig for real himself," says co-star John C. Reilly.

But nothing could have readied Miller for her husband's next role as an obsessive loner in the upcoming family drama Rose and the Snake -- she's the director.

"We haven't actually worked together before, so I'll have to tell you what it's like when we're done," she told The Post from the couple's home in County Wicklow, Ireland.

Miller should be prepared to say goodbye to the polite and kind father of their two small sons -- and hello to a dropout who lives with his 16-year-old daughter on an abandoned commune on an island off the coast of Canada.

Day-Lewis is typically so intent on immersing himself in a part that he refuses to break character -- not in between takes or even, occasionally, after hours.

No matter how hairy the experience gets, the sweet-tempered writer-director has this film to thank for bringing her and Day-Lewis together in the first place.

Miller -- whose female-empowerment indie Personal Velocity is up for an Independent Spirit Award this month -- wrote the screenplay for Rose and the Snake, about seven years ago -- and immediately thought of Day-Lewis for the male lead.

"I had sent the script to him before we even met, when I first wanted to get the movie made," Miller says.

"He wasn't able to do it then, but it was one of the reasons he went and saw my first film, 'Angela.'"

Miller and Day-Lewis met at the Connecticut home of her father, playwright Arthur Miller, while the two men were working on the 1996 film version of The Crucible.

They were wed in a secret ceremony in November 1996, and the relationship has been credited with bringing order and calm to the famously volatile actor's life.

Miller has even succeeded in getting her husband to lighten up -- the two have recently co-written a screenplay for a comedy -- and says she's "excited" about working with him in Canada later this year.

Asked recently about working with co-star Leonardo DiCaprio on Gangs, Day-Lewis told reporters, "We kept the right distance. On film sets, people tend to reach out -- there's something dangerous in that."

We trust he'll make an exception for his wife.