They were hailed as all-American heroes when they pummeled a heavily-armed jihadist with their bare hands to foil the Thalys train terror attack in France in 2015.
But the three childhood friends who play themselves in Clint Eastwood's Hollywood reconstruction of the drama took a battering from critics when the film opened in France on Wednesday.
"We thought the projectionist had put on the wrong film for the first quarter of an hour," said the Parisien newspaper, which bemoaned how the veteran director took an hour and 15 minutes to recount the friends' "tedious" childhoods as devout Catholics in California.
Only in the final "incredible, hyper-tense 10 minutes" does "The 15:17 to Paris" take off, said critic Renaud Baronian when Spencer Stone, Alek Skarlatos and Anthony Sadler overpower a Moroccan jihadist armed with an AK-47 on the Paris-bound train from Amsterdam carrying more than 500 passengers.
Others were slightly less damning, with one critic lamenting that "an incredible story does not make a good film" and that "the movie gets stuck in the station," while Culturebox said with biting irony that "it was not going to revolutionise cinema."
The Figaro newspaper, however, praised it, although it admitted it "does not play the suspense card".
Warner Brothers had not shown the film to critics in advance, as is the usual practice, "which is generally a sign that it is a bad film," Nick James, editor of Britain's Sight & Sound magazine, told AFP.
- 'We wanted to be exact' -
The movie's trio of friends were reunited with members of the emergency services crews who tended the injured after the attack at a special screening in Paris last week.
Some of them were also recruited by Eastwood, 84, to play themselves in the drama.
"I hope you like the film. We wanted to be exact about what happened," said Skarlatos, 25, an Oregon National Guardsman who served in Afghanistan.
US Air Force Airman Spencer Stone charged at Ayoub El Khazzan after he wounded another passenger and managed to disarm him of the AK-47 and of a pistol which jammed as El Khazzan tried to shoot him.
Stone was slashed with a bolt cutter around the neck as Skarlatos and Sadler knocked the attacker unconscious and then "hog-tied" him.
The three were hailed as heroes both in the United States and in France, where they were awarded the Legion of Honour, the country's highest decoration.
But the film has raised the hackles of El Khazzan's lawyers, with judges yet to deliver their verdict.
"That Hollywood has delivered its 'truth' before the judges is at the very least worrying," Sarah Mauger-Poliak told French radio.
The film -- which opens in cinemas in the US and the UK on Friday -- follows the course of the friends' lives, from their childhood struggles to the series of unlikely events leading up to the thwarted attack.
- 'We could all be dead' -
Hollywood legend Eastwood's last two films -- "Sully" and "American Sniper" -- were also about real-life heroes, but this is the first time he has used the real protagonists to play themselves.
A former Republican politician, who makes no apology for his gung-ho patriotism, Eastwood said he wanted to "make people aware that they have the strength to do (extraordinary) things themselves.
"There could have been a lot of people killed, (the attacker) had a lot of ammunition, he had a very reliable gun," he said in a filmed interview with the cast released to promote the movie.
"Eastwood has always been interested in Average Joes who find themselves at the centre of great events," said James. "As far as he is concerned there is no need to make America great again, because America has always been great."
Skarlatos, who appeared on the "Dancing With the Stars" US television show after the attack, said that "knowing each other since we were very young, it was the icing on the cake that we got to play ourselves.
However, "if anything went differently we would probably all have been dead," he added.