When Marla and Lucy share the back seat of a car, much of their dialogue is improvised.
Warren Beatty turned down an offer of $1 million to play Howard Hughes in the TV miniseries "The Amazing Howard Hughes" thus enabling Tommy Lee Jones to star as Howard Hughes. That was one of Tommy Lee Jones' early break out parts.
Warren Beatty first pitched a Howard Hughes biopic as early as 1973. He continually tried to get a film involving Hughes off the ground every year or two since then. It could be said that it is a film forty years in the making.
Warren Beatty was 79 when he played Howard Hughes. The real Howard Hughes died at the age of 70.