Fønss' leading role in the 1913 Danish classic Atlantis made his face recognizable to movie fans. It was his role as the mad-scientist in the 1916 German science fiction film series, Homunculus, that earned Fønss status as a top matinee idol. In the 1930s, Fønss became politically active by directing two films for Denmark's Socialdemokratiske Parti (Social Democracy Party), Den Store Dag (1930) and Under Den Gamle Fane (1932). He was president of the Danish Actor's Union from 1933–1947 and was a censor for the National Film Censor of Denmark for 14 years. Fønss was the older brother of actors Johannes and Aage Fønss.
As Director
Hævneren (1919)
Samvittighedskvaler (1920)
B.T.'s amatørfilm (1923)
Den store Dag (1930)
Under den gamle Fane (1932)
Filmography
Actor
1932
Vask, videnskab og velvære
1929
Die seltsame Vergangenheit der Thea Carter as
Direktor Carter (as Olaf Fönss)
1929
Triumph of Love as
Fürst Wronsky
1926
Die Waise von Lowood as
Lord Edward Rochester (as Olaf Fönss)
1926
Spitzen
1925
Fra Piazza del Popolo as
Olaf Malm
1923
Das unbekannte Morgen
1923
Republikaneren as
Dr. Michael Orloff
1922
Timeglasset
1921
Mysteries of India, Part II: Above All Law as
Herbert Rowland (as Olaf Fönss)
1921
Mysteries of India, Part I: Truth as
Herbert Rowland (as Olaf Fönss)
1921
Hendes fortid as
Prof. Kurt van Horn
1921
Ehrenschuld
1921
Munkens fristelser as
Bengt Darre / Friar Benedetto
1921
Journey into the Night as
Dr. Eigil Börne
1920
Samvittighedskvaler
1920
En Aftenscene as
Prof. Ole Borch
1919
Die Totenmaske
1919
Dømmer ikke as
DA Bloomer / Geert Jerome
1919
Scenens Børn as
Axel Steiner - Famous Actor
1919
Hævneren as
Poul Hamrik
1919
Das Gelübde der Keuschheit
1919
Bajadser as
Canio
1919
Lykkeper as
Skipper Peter Storm - Lykkeper
1918
Love Your Neighbor! as
Strøm - Vicar
1918
Dommens dag as
Baron van Straeten
1918
Skæbnesvangre vildfarelser as
Gaston Printemps - billedhugger
1918
Fangen fra Erie Country Tugthus
1918
Livets Stormagter as
Ingo Theoso
1918
Lægen as
Dr. Harold Lister
1918
Du skal ære as
Frantz Gerner
1917
Gengældelsens ret as
Jan Hemkirk
1917
En ensom Kvinde as
Dr. Heppel
1917
Homunculus, 4. Teil - Die Rache des Homunculus as
Richard Ortmann - der Homunculus
1917
Homunculus, 6. Teil - Das Ende des Homunculus as
Richard Ortmann - der Homunculus
1916
Hendes ungdomsforelskelse as
James Geary - Archeologist
1916
Homunculus, 5. Teil - Die Vernichtung der Menschheit as
Richard Ortmann - der Homunculus
1916
Homunculus, 3. Teil - Die Liebeskomödie des Homunculus as
Richard Ortmann - der Homunculus
1916
Homunculus, 2. Teil - Das geheimnisvolle Buch as
Richard Ortman - der Homunculus (as Olaf Fönss)
1916
Homunculus as
Homunculus
1916
Barnet fra Opfostringshuset (Short) as
Dick Harris
1916
Homunculus, 1. Teil as
Homunculus
1916
Selskabsdamen as
Robert Foch
1916
Den omstridte Jord as
Harry Blom
1916
Naar Hjerterne kalder as
Felix Saltau
1916
Lotteriseddel No. 22162 as
Mr. Brown
1916
The End of the World as
Frank Stoll - Mine Owner
1916
Gentlemansekretæren as
Sir John Gladwin
1916
Syndens datter as
Henry Born
1915
Cowboymillionæren as
Tim Roger
1915
Lille Teddy as
Chas Barley
1915
Den hvide rytterske as
Willi Cornel
1915
En Død i Skønhed as
Prof. Benno
1914
Down with Weapons as
Fr. von Tilling, Marthas anden mand
1914
En stærkere magt as
Egil Holck
1914
Skyldig? - Ikke skyldig? (Short) as
Alexander Hempel
1914
A Deal with the Devil (Short) as
Walter Fahrich - Student
1914
Guldkalven (Short) as
Richard Williams - guldgraver
1914
Was She Justified? as
Dommer
1914
Vasens Hemmelighed as
Gregers Marcher
1914
Count Zarka (Short) as
Prince Roel
1913
Amerikansk skoleskib (Short)
1913
Atlantis as
Dr. Friedrich von Kammacher
1913
Troløs (Short) as
Mr. Wartley
1913
Paradise Lost as
Gerhard von Borch
1913
His Unknown Brother (Short) as
Olaf
1913
Af en Opdagers Dagbog (Short) as
John Higgins / John Warming
1913
Krigens Fakkel (Short)
1913
Under mindernes træ (Short) as
Simon Durand - Painter
1913
The Grain Speculator (Short) as
Dr. Maclaren
1913
Pressens Magt (Short) as
Freddy Malwood
1912
Konfetti (Short) as
Morin - Therese' Fiancé
1912
Zigeunerorkestret as
Carlo, Bjørnetoemmeren
1912
Bryggerens datter as
Erik Holk
1912
The Leap to Death (Short) as
Stacy Black
Director
1932
Under den gamle fane (Documentary)
1930
Den store dag (Documentary)
1923
Bag Filmens Kulisser
1920
Samvittighedskvaler
1919
Hævneren
Writer
1930
Den store dag (Documentary)
Self
1938
Olaf Fønss (Documentary) as
Self
1932
Under den gamle fane (Documentary)
Archive Footage
1998
Dämonische Leinwand - Der deutsche Film der zwanziger Jahre (Documentary) as
Dr. Eigil Börne (clip from Der Gang in die Nacht (1921)) (uncredited)