|Directed by||Joseph Pevney|
|Produced by||Albert J. Cohen|
|Written by||Barbara Gray|
Richard Alan Simmons
|Screenplay by||Seton I. Miller|
|Story by||Seton I. Miller|
|Cinematography||William H. Daniels|
|Edited by||Sherman Todd|
|Distributed by||Universal Pictures|
|Box office||943,679 admissions (France)|
Istanbul is a 1957 American CinemaScope Technicolor film noir crime film directed by Joseph Pevney, and starring Errol Flynn and Cornell Borchers. It is a remake of the film Singapore, with the location of the action moved to Turkey. The plot involves an American pilot who becomes mixed up with various criminal activities in Istanbul.
For the first time in five years, pilot Jim Brennan (Errol Flynn) flies to Istanbul, Turkey, but is immediately brought to the office of customs Inspector R. P. Nural (John Bentley) who suspects him of diamond smuggling. Jim goes to the hotel where he stayed previously, but his old room has American couple Charlie (Leif Erickson) and Marge Boyle (Peggy Knudsen) staying there.
At the café, Jim sits at his regular table and recalls the last time he was there, sharing a drink with German tourist Stephanie Bauer (Cornell Borchers), a beauty with whom he falls in love. She knows he has to fly for a living, and encourages him to accept a quick job flying businessmen to Cairo. On his return, an old friend, merchant Aziz Rakim (Vladimir Sokoloff) offers Jim a bracelet to give to Stephanie but a hidden compartment contains diamonds, which Jim stashes in his ceiling fan.
When he proposes to Stephanie, he also gives her the bracelet. She accepts his proposal, but back at his room, the couple encounter Paul Renkov (Werner Klemperer) who is looking for the diamonds. The next night, Paul follows Jim and with several henchmen, beat him up. Mr. Darius (Martin Benson), their leader, demands the diamonds. The police find Jim, and at headquarters, Nural tells him that Aziz was murdered likely due to his role in a shipment of stolen diamonds smuggled in a bracelet. Jim denies involvement in the theft and later asks Stephanie to come with him that night to Paris.
At her hotel room, Darius' men accost Stephanie and steal the bracelet. Jim finds Nural in his room, and reveals that he has impounded his aircraft and plans to keep him in custody until Jim leaves the country. Knowing he cannot retrieve the diamonds, Jim and Nural go to Stephanie's hotel, but the building is in flames. Jim tries to save his fiancée, but the blaze forces him to retreat.
Years later, Renkov finds Jim and tells him Darius wants to get his diamonds. Jim knows the married couple in his old room are in danger, and goes to the hotel, but is amazed to see Stephanie there. Claiming to be Karen Fielding, she leaves with her husband, Douglas Fielding (Torin Thatcher), the man who had saved her five years ago when her hotel had caught on fire. She had lost all of her earlier memories and does not recognize Jim.
Jim tries to press Stephanie about her past, but her husband asks him to leave them in peace. Later, clutching the bracelet Jim gave her, she secretly visits him at the café, trying to remember what he meant to her once. Jim attempts to retrieve the diamonds but is nearly caught by the inspector. He slips them into one of the Boyle's suitcases. Leaving the room he allows himself to be captured by Renkov and taken to an abandoned warehouse where Darius has already kidnapped Stephanie. Convincing Darius that she is the real thief, Jim slyly sets the warehouse ablaze.
Grabbing Stephanie who has gone into shock, he takes her back to her husband but the next morning as he prepares to fly out of Istanbul, Stephanie suddenly awakes and calls out Jim's name. Rushing to the airport, they see that Jim is caught with the diamonds although Nural decides to let him leave the country. As the aircraft takes off, her husband sees Stephanie's reaction and with the inspector's help, Jim is ordered to come back to Istanbul as someone wants to reunite with him.
- Errol Flynn as James Brennan
- Cornell Borchers as Stephanie Bauer / Karen Fielding
- John Bentley as Inspector Nural
- Torin Thatcher as Douglas Fielding
- Leif Erickson as Charlie Boyle
- Peggy Knudsen as Marge Boyle
- Martin Benson as Mr. Darius
- Nat "King" Cole as Danny Rice
- Werner Klemperer as Paul Renkov
- Vladimir Sokoloff as Aziz Rakim
- Jan Arvan as Kazim
- Nico Minardos as Ali
- Ted Hecht as Lt. Sarac
- David Bond as Dr. Sarica
- Roland Varno as Mr. Florian
- Hillevi Rombin as Air Hostess
It was the first film Errol Flynn had made in Hollywood for a number of years, since Against All Flags (1952). Universal also considered Jeff Chandler to play "Jim Brennan" and Robert Middleton to play "Mr. Darius." 
Cornell Borchers was already attached to the film when Flynn signed on. It was the second of two films Borchers made for Universal. Universal were very big on hiring stars with international reputations at the time.
Istanbul marked Peggy Knudsen's last film appearance.
Kim Inc., which had the rights for a 1954 film called Istanbul starring Virginia Bruce, brought a suit against Universal claiming $450,000 in damages and an injunction stopping use of the name Istanbul. This was dismissed. Istanbul was released on VHS home video (1996) and on DVD with "Singapore" as a 2-film set, but currently unavailable.
Bosley Crowther in his review for The New York Times, described Istanbul, as basically mediocre. "There is nothing to distinguish this production. The color is good and the CinemaScope inserts of the city by the Golden Horn are nice."
- "1957 French box office." Box Office Story. Retrieved: November 27, 2015.
- "Review: 'Istanbul'." British Film Institute (BFI). Retrieved: November 27, 2015.
- Scheuer, Philip K. "Errol claims he's now in like Flynn with creditors." Los Angeles Times, March 4, 1956, p. E2.
- Pryor, Thomas M. "Widmark to star as independent; will make 2 films for Heath Productions that United Artists will distribute; Jerry Waid's plans." The New York Times, February 8, 1956, p. 39.
- "Star Dust." The Mirror (Perth), April 28, 1956, p. 11 via National Library of Australia. Retrieved: May 17, 2012.
- Hopper, Hedda. "Now it's family man Flynn!" Chicago Daily Tribune May 27, 1956, p. h28.
- Thomas et al. 1969, p. 208.
- Pryor, Thomas M. "Metro will film 'Silk Stockings'; Studio assigns musical hit to Arthur Freed, who is studying show here; Flynn and U.I. resume." The New York Times, February 16, 1956, p. 25.
- Hopper, Hedda. "Errol's a family man now, Errol Flynn settling down to new role as family man Los Angeles Times, May 27, 1956, p. E1.
- Hopper, Hedda. "Cornell Borchers, "world wide star; popular German actress has movie making contracts on three continents." Chicago Daily Tribune, June 17, 1956, p. g26.
- Scheuer, Philip K. "A town called Hollywood: singer Eddie Fisher still doesn't think he's an actor." Los Angeles Times, August 19, 1956, p. E2.
- Pryor, Thomas M. "Film partnerships formed at M-G-M: producers Weingarten and Berman to make movies independently for studio move comes Late." The New York Times, February 26, 1957: p. 26.
- Crowther, Bosley. "Movie review: 'Istanbul' (1957); The screen: 'Istanbul'; Errol Flynn appears in Palace film." The New York Times, January 24, 1957
- Maltin 2009, p. 693.
- Maltin, Leonard. Leonard Maltin's Movie Guide 2009. New York: New American Library, 2009 (originally published as TV Movies, then Leonard Maltin’s Movie & Video Guide), First edition 1969, published annually since 1988. ISBN 978-0-451-22468-2.
- Thomas, Tony, Rudy Behlmer and Clifford McCarty. The Films of Errol Flynn. New York: Citadel Press, 1969.