Jennifer Connelly lost 25 pounds (11.3 kilograms) to play a homeless woman in her real-life husband Paul Bettany's directorial debut.

The Noah star really jumped into the world of the displaced to research her role as Hannah in Shelter, and as well as learning how to use needles and drug paraphernalia and spending time with addicts, she also underwent a drastic weightloss to look gaunt for the part.

She tells Wenn, "There was so much to work to do about her (Hannah) and the circumstances of her life that I knew nothing about. I had a lot of practical research to do. Slowly, over months, I lost a lot of weight and ultimately lost about 25 pounds.

"I wanted to be quite comfortable with her and I had no experience of using needles, so I spent a lot of time working on that so I could be quite at ease; practising using the paraphernalia.

"There's an organisation called Coalition for the Homeless in New York City, which is a phenomenal organisation and they were very generous with their time. Also, my character is an intravenous drug user so I spent a lot of time with people who are currently struggling with addiction, with doctors who are experts on addiction and some recovered addicts who shared their stories with me and worked with me closely on the script.

"Another organisation, called Lower East Side Home Reduction Center, was also very useful to me with their outreach programmes. We'd walk around Astor Place and Tompkins Square Park at night (in the East Village) and got ideas from people I met. I watched a lot of documentaries and looked at images and photos to see what her skin would look like and what her arms would look like. It was pretty quite specific."

But her research was also distressing, because she came face to face with the shocking homeless statistics, adding, "The sheer numbers are quite striking. I had no idea. For me it was quite revelatory to realise how many children are homeless in New York; 56,000 people each night in New York City are in shelters alone. So those numbers are quite staggering and that doesn't count for people who are sleeping rough, sleeping in the streets and not in shelters."