After a cancer operation in 1955, which resulted in a slight disfiguration of her face, directors shied back from casting her as romantic heroine.

Among her most notable appearances on the silver screen was the part of Klothilde in the 1959 cinema adaptation of Thomas Mann's classic novel Buddenbrooks.

In the late 1960s, Feddersen discovered her writing talent, and over the next fifteen years she wrote the scripts for several successful made-for-TV movies and mini series, most of them portraying the hard but hopeful lives of sailors, shipyard workers, fisher men and their families in the port of Hamburg and along the river Elbe as well as the German North Sea Coast.

During the late 1970s, she hosted several comedy shows and enjoyed a smash hit in 1978, when she teamed up with Dieter "Didi" Hallervorden for the duet Du, die Wanne ist voll (The bathtub's full), a chart topping spoof cover version of You're the One That I Want from the movie Grease.

In 1981, Feddersen enjoyed a solo # 1 on the German charts with Gib mir bitte einen Kuss (Please, give me just one kiss), a spoof vocal version of the Chicken Dance.

Her guest appearance as a courageous policeman's widow in the long-running series Großstadtrevier (famous for its authentical portrayal of policemen's work and private lives), though, became the last role she ever played.

Helga Feddersen is still remembered and recognized in Germany as a talented actress and a loveable, warm-hearted person.