By Mike Collett-White

LONDON (Reuters) - Hollywood actress Gwyneth Paltrow is on the comeback trail after a break from acting, appearing in "The Good Night" directed by younger brother Jake.

The 34-year-old, who won a best actress Oscar for the 1998 film "Shakespeare in Love", admitted she was nervous about being shunned by the industry after three years away looking after her two children.

And while she is ready to return to regular work, it will be at a slower pace than her pre-motherhood days.

"I really stopped working for three years and I really wanted to be at home with my kids, and I still do. But there's also part of me that is an artist," she said in an interview with her brother to publicise "The Good Night".

"But it's hard, it's always hard to get the balance of it all right," she told Reuters.

Paltrow is also slated to appear in "Iron Man" alongside Robert Downey Jr., due in theatres next year.

"So I'm going back to work, definitely, and I'm really excited about it. But I won't work at the pace that I used to work -- I won't do three, four films a year, it'll be more like one, one-and-a-half films a year."

The actress, married to British pop star Chris Martin with whom she has two children, was concerned that her time away from the film set could hurt her career.

"I was worried that everybody would have forgotten about me, so there was an ego thing involved as well.

"Will I actually be able to go back to work if I want to go back? Will there be parts for me? Will people care? And you know, so far they kind of seem to care, I'm getting some interesting jobs, it's fun, it's nice to be working again."

DIRECTORIAL DEBUT

First-time director Jake Paltrow, three years Gwyneth's junior, said his sister was the last major role he cast for his dark romance "The Good Night", so concerned was he that the project would be "eclipsed" by his famous sibling.

Spanish actress Penelope Cruz, Britain's Martin Freeman and U.S. comedian Danny DeVito were all on board first, he added.

"It's just I didn't want her involvement to eclipse the movie, and I didn't want to seem like the movie was getting made only because she was in it."

With the film about to be released in the United States in early October, he is bracing himself for some scepticism.

"I'm perfectly prepared for any sort of ... negative response to that. What can I do about it?"

Gwyneth plays Dora, the dark-haired and downbeat girlfriend of Gary (Freeman), a former pop star now writing commercial jingles for a living and stuck in a mid-life rut.

He dreams of Anna (Cruz), a mysterious beauty who fulfils his sexual fantasies, but when he meets her in the flesh their brief friendship goes nowhere.

"Here is a feeling about chasing perfection that a lot of people can identify with," said Jake, describing Gary. "His ideas of self-perceived failure are very strong."

Early reviews of "The Good Night" have been mixed. The Hollywood Reporter said the film "just makes you sleepy", while rival publication Variety called it "enchanting", and with the potential to be a surprise hit.