In 1979, a group of Turkish and Italian filmmakers and actors began working on a clone to the 1978 Superman film, this time not using Christopher Reeve, but Cüneyt Arkın, a popular Turkish movie star that is also famous for starring in 1982's Dünyayı Kurtaran Adam (The Man who Saved the World), a sci-fi adventure better known by many as "Turkish Star Wars" because of its use of stolen footage from Star Wars.
This superhero film also features some science fiction elements, and it was known as Süpermenler, whose title is translated to English as Supermen. Here's how the film's plot works:
A German professor builds a time machine that he would use as an attempt to recover the Byzantine treasury, which was lost during the Fall of Constantinople. Murat, a police detective, leads his band of crime-fighting superheroes, known as the "Süpermenler", to fight off a mafia, who tries to fight the professor for the right to claim ownership for the time machine. Luckily, the team helps the German scientist, and they saved the world.
The film was a cult classic, and was similar to another Turkish Superman mockbuster released a year earlier in 1978, and was entitled Süpermen Dönüyor (The Return of Superman). Süpermen Dönüyor had the same Superman, except that he was raised in Turkey, given the name Tayfun instead of Clark Kent (what's funny about this mockbuster is that Krypton was shown as a Christmas ornament against a background of Christmas ornament stars, and that the flying effects consisted of a Superman doll being dragged with a fishing line, while being on a film-projected background!). The reason why both of these Superman clones were made was because the original Superman movie didn't appear in Turkish movie theatres, along with some other American superhero/sci-fi classics, because of Turkey's terrible political state.
This could be the best Turkish superhero film in the history of the 1970's-1980's, depending on how much of a cult classic it can be. VHS copies of this movie might fetch for over $100 on eBay, but it might be easily available through websites like YouTube or, for those who don't want to pay, the Pirate Bay.