His most famous credited role is the one in Il gattopardo (1963), but he is credited too in Killer Kid (1967) as Nelson Rubien, in L'età di Cosimo De' Medici (1972) as Honard Nelson Rubien.
But the majority of the time he is uncredited.
- Che gioia vivere .... Officer at airship launch (uncredited)
- Il pianeta degli uomini spenti .... United Commission representative (uncredited)
- Il Re di Poggioreale .... Professor who asks for penicillin (uncredited)
- Una vita difficile .... Eccellenza, party guest (uncredited)
1962 - Boccaccio '70 .... Restaurant diner (uncredited)
- Il sorpasso .... Man waiting in toilet door (uncredited)
- L'orribile segreto del Dr. Hichcock .... Laboratory specialist (uncredited)
- La marcia su Roma .... Professor Bellinzoni (credited as "Howard Rubiens")
- Maciste all'inferno .... Villager (uncredited)
1963 - I 4 tassisti .... Man asking questions (uncredited - uncertain identification)
- Il Gattopardo .... Don Diego (credited as "Howard N. Rubien")
- Maciste contro i Mongoli .... Mongol elder at Khan's funeral (credited as "Rubien Howard")
- Tempo di Roma .... Tourist (uncredited)
1964 - Extraconiugale .... Man in Renato's home movie (uncredited)
1965 - Due mafiosi contro Goldginger .... General (uncredited)
- Io uccido, tu uccidi - segment "Giochi acerbi" .... The count, a guest at the memorial service (uncredited)
1966 - Bel Ami 2000 / 100 ragazze per un playboy .... Party guest (uncredited)
- Che notte ragazzi! .... Brown the elder (uncredited)
- Io, io, io... e gli altri .... Politician (uncredited)
- Ramon il Messicano .... The doctor (uncredited)
- Requiem per un agente segreto .... The professor (uncredited)
- Scusi lei è favorevole o contrario? .... Party guest (uncredited)
1967 - Killer kid .... El Santo (credited as "Nelson Rubien")
1969 - Cuore di mamma .... Dean of the university (uncredited)
- La caduta degli dei .... General (credited as "H. Nelson Rubien")
1971 - Morte a Venezia .... Hotel guest (uncredited)
- Stress .... Marquis (uncredited)
1972 - Fratello Sole, Sorella Luna .... Priest (uncredited)
- L'età di Cosimo de' Medici (TV mini series) - ep. 3 .... Giorgio Gemisto Pletone (credited as "Honard Nelson Rubien")
- Ludwig .... Ambassador (uncredited)
1973 - Canterbury n.2 .... First storyteller (uncredited)
- Pane e cioccolata .... Restaurant customer (uncredited)
- Tutti figli di mammasantissima ... Corrupt senator (uncredited)
1975 - Mahogany .... Man at fashion show (uncredited)
1976 - A Matter of Time .... Disgruntled hotel guest (uncredited)
- Cassandra Crossing .... Train passenger (uncredited)
- Cuore di cane .... Professor's guest (credited as "Nelson Rubien")
- L'innocente .... Party guest (uncredited)
- Oh, Serafina! .... Grandfather of Augusto Valle (uncredited)
- Spogliamoci così senza pudor .... Friend of the Partibon family (uncredited)
1978 - Le braghe del padrone .... Elegant man in car (uncredited)