The state-run Anadolu news agency said Ali Avci was detained on suspicion of links to the group blamed by Ankara.
The state-run Anadolu news agency said Ali Avci was detained on suspicion of links to the group blamed by Ankara for the -- real life -- failed coup that sought to oust Erdogan last year.
Avci's new film "Uyanis" (Awakening) is not in theatres yet but its trailer has already stirred up controversy on the first anniversary of the July 15 attempted putsch Ankara says was masterminded by US-based Muslim preacher Fethullah Gulen.
Gulen denies the charges.
Police also detained another man, identified as Fetullah Karabiber, who was found in Avci's house and was already wanted by authorities, it said.
Uyanis's trailer features the killing of Erdogan's family -- including his wife Emine and his son Bilal -- in their house in the Kisikli district of Istanbul while Erdogan is shown under gunpoint.
Avci was also a producer of the film "Reis" (the Chief), a biopic about Erdogan's early political life, which hit screens ahead of a key April referendum to boost Erdogan's powers.
It was the first ever feature film about Erdogan and received immense media attention at home and abroad ahead of its release.
However, it garnered dreadful reviews and made only paltry box office takings. Turkish media reported that Erdogan did not watch that film.