Donohoe at first came to attention of the worldwide audience in 1986 when girl was cast opposite Oliver Reed as Lucy Irvine in Nicolas Roeg's Castaway (where she appeared nude in some momments of the films). Celeb followed this up with roles in 2 Ken Russell movies The Lair of the White Worm, based on a Bram Stoker novel, and The Rainbow, based on a D.H. Lawrence novel. In 1981, Amanda appeared in the music movie for the song, (Stand and Deliver) by Adam and the Ants.

In 1993 she ranked 16th in Celebrity Sleuths 25 Sexiest and in 1995 she ranked 16th in FHM's 100 Sexiest Women.

She won a Golden Globe for her role in LA Law and was nominated for an Outer Circle Critics Award for her Broadway debut in Uncle Vanya.