The two actors did whatever was required of them. Kidman undresses multiple times on screen and Cruise is put through all manner of indignities, from having his wife verbally rip him apart to being tossed into the middle of a fray between Japanese businessmen...
It was just the trailers that did it for me. I can't look at a doll with those googly glass eyes the same way since. My older cousins played on this fear one time. In my grandfather's scary old basement, he had a typewriter. One of them typed on a page, "Chucky's going to ...