He worked as a theatre manager and journalist until 1938 when he was hired by Suomi-Filmi, a company he would stay with for the remainder of his career.
[1] He wrote the scripts for Jääkärin morsian (1938) and Aktivistit (1939), but quickly transitioned into the director's chair, with the comedies Punahousut (1939) and Kersantilleko Emma nauroi?
[2] Among the most important of these were the biopics of author Aleksis Kivi and opera singer Abraham Ojanperä, Minä elän (1946) and Ruusu ja kulkuri (1948).
The film historian Peter von Bagh also lists Härmästä poikia kymmenen (1950), Pimeänpirtin hävitys (1947), Koskenkylän laulu (1947), and Kanavan laidalla (1949) among the director's most notable works.
[1] Unho usually wrote the screenplays for his own films and continued to write scripts for other directors throughout his career.