| IIl giorno del giudizio1994 · Writer | Writer |
 Casablanca Express1989 · Screenplay | Screenplay |
| JJiboa1989 · Writer | Writer |
 Stradivari1988 · Screenplay | Screenplay |
 The Shatterer1987 · Screenplay | Screenplay |
| PProvare per credere1987 · Writer | Writer |
 Hands of Steel1986 · Screenplay | Screenplay |
 The Killer Is Still Among Us1986 · Screenplay | Screenplay |
 2019: After the Fall of New York1983 · Screenplay | Screenplay |
 Scorpion with Two Tails1982 · Screenplay | Screenplay |
 Lo Scorpione a Due Code1982 · Writer | Writer |
 Screams in the Night1981 · Director, Writer | Director, Writer |
 I'm Getting a Yacht1980 · Screenplay | Screenplay |
 The Great Alligator1979 · Writer | Writer |
 Concorde Affair1979 · Screenplay | Screenplay |
 Sahara Cross1977 · Screenplay | Screenplay |
 The Cynic, the Rat & the Fist1977 · Screenplay | Screenplay |
 A Genius, Two Friends, and an Idiot1975 · Screenplay | Screenplay |
 Savage Three1975 · Screenplay | Screenplay |
 Kidnap Syndicate1975 · Screenplay | Screenplay |
 The Suspicious Death of a Minor1975 · Screenplay | Screenplay |
 Gambling City1975 · Screenplay | Screenplay |
 Gun Moll1975 · Writer | Writer |
 Puzzle1974 · Screenplay | Screenplay |
 Almost Human1974 · Screenplay | Screenplay |
 My Name Is Nobody1973 · Screenplay | Screenplay |
 Anna: the Pleasure, the Torment1973 · Screenplay | Screenplay |
 The Violent Professionals1973 · Screenplay | Screenplay |
 Torso1973 · Screenplay | Screenplay |
 The Grand Duel1972 · Screenplay | Screenplay |
 A Reason to Live, a Reason to Die1972 · Screenplay | Screenplay |
 Death Walks at Midnight1972 · Screenplay | Screenplay |
 The Case of the Bloody Iris1972 · Screenplay | Screenplay |
 Your Vice Is a Locked Room and Only I Have the Key1972 · Screenplay | Screenplay |
 Prey of Vultures1972 · Screenplay | Screenplay |
 All the Colours of the Dark1972 · Screenplay | Screenplay |
 Death Walks on High Heels1971 · Screenplay | Screenplay |
 The Case of the Scorpion's Tail1971 · Screenplay | Screenplay |
 Human Cobras1971 · Screenplay | Screenplay |
 The Lonely Violent Beach1971 · Director, Writer | Director, Writer |
 The Strange Vice of Mrs Wardh1971 · Screenplay | Screenplay |
 Light the Fuse… Sartana Is Coming1970 · Screenplay | Screenplay |
 The Forbidden Photos of a Lady Above Suspicion1970 · Screenplay | Screenplay |
 So Sweet... So Perverse1969 · Screenplay | Screenplay |
 Desert Assault1969 · Writer | Writer |
 The Battle of El Alamein1969 · Screenplay | Screenplay |
 Diamonds for Breakfast1968 · Writer | Writer |
 To Hell and Back1968 · Screenplay | Screenplay |
 Cheers... Cyanide!1968 · Director, Screenplay | Director, Screenplay |
 Taste of Vengeance1968 · Screenplay | Screenplay |
 The Sweet Body of Deborah1968 · Writer | Writer |
 Day of Anger1967 · Screenplay | Screenplay |
 Vengeance Is Mine1967 · Screenplay | Screenplay |
 Flashman1967 · Writer | Writer |
 $10,000 for a Massacre1967 · Screenplay | Screenplay |
 Your Turn to Die1967 · Screenplay | Screenplay |
 $1,000 on the Black1966 · Writer | Writer |
 Ring Around the World1966 · Screenplay | Screenplay |
 Arizona Colt1966 · Screenplay | Screenplay |
 Where Are You Taking That Woman1966 · Screenplay | Screenplay |
 Almost Perfect Crime1966 · Screenplay | Screenplay |
 Fury in Marrakesh1966 · Writer | Writer |
 The Murder Clinic1966 · Screenplay | Screenplay |
 Killers Are Challenged1966 · Screenplay | Screenplay |
 Special Code: Assignment Lost Formula1966 · Writer | Writer |
 Libido1965 · Director, Screenplay, Producer | Director, Screenplay, Producer |
 Secret Agent Fireball1965 · Screenplay | Screenplay |
 The Revenge of the Gladiators1964 · Writer | Writer |
 Giants of Rome1964 · Screenplay | Screenplay |
 The Monster of the Opera1964 · Screenplay | Screenplay |
 Crypt of the Vampire1964 · Screenplay | Screenplay |
 Scandal Nudes1963 · Screenplay | Screenplay |
 Hercules and the Masked Rider1963 · Writer | Writer |
 The Whip and the Body1963 · Screenplay | Screenplay |
 Horror Castle1963 · Screenplay | Screenplay |
 Divorzio alla siciliana1963 · Screenplay | Screenplay |
 Son of Hercules vs. Medusa1963 · Screenplay | Screenplay |
 Alone Against Rome1962 · Screenplay | Screenplay |
 The Horrible Dr. Hichcock1962 · Writer | Writer |
 Last Chance for Life1962 · Writer | Writer |
 Pesci d'oro e bikini d'argento1961 · Screenplay | Screenplay |
 Werewolf in a Girls' Dormitory1961 · Writer | Writer |
 Rocco e le sorelle1961 · Screenplay | Screenplay |
 Che femmina!! E... che dollari!1960 · Screenplay | Screenplay |
 The Vampire and the Ballerina1960 · Screenplay | Screenplay |
