Four Lions follows four men plotting to kill thousands at the London Marathon
Some families who lost relatives in the 2005 London bomb attacks are appealing to cinemas not to show a British comedy about four aspiring suicide bombers.
Four Lions, created by satirist Chris Morris, focuses on four men travelling to London to target the marathon.
Graham Foulkes, whose son was among the 52 killed on 7 July 2005, said that, with the tragedy still raw, the film was too closely aligned to real events.
The film's producers said they "did not seek to cause any offence".
Mr Foulkes, whose 22-year-old son David was on the Tube train targeted at Edgware Road, told BBC Radio 5 live that parody and satire had a part to play in examining serious issues
"But here, what he's done, he's taken a specific attack," he said.
He said the film was about "four lads from the north, all with strong Yorkshire accents - and the bombers were from Yorkshire - travelling down to London".
It's very aligned to what happened in 2005 and they talk about bombing in London. That's not parodying or being satire about terrorists
"It's very specific. It's very aligned to what happened in 2005 and they talk about bombing in London.
"That's not parodying or being satire about terrorists. It's making money about a specific attack."
Mr Foulkes, who said he had watched clips of Four Lions online, said he and other relatives of victims were calling on cinemas to boycott the British-funded film.
Makers Warp Films said in a statement: "The film does not mock or trivialise the suffering caused by bombings.
"We sympathise with those affected by the events of 7 July and did not seek to cause them any offence."
Chris Morris, who was also behind the controversial Channel 4 series Brass Eye, says the film shows "the Dad's Army side to terrorism", as four incompetent jihadists plan an attack.
The think-tank Demos said by ridiculing the aims of terrorists, the film was a "critical weapon in the fight against terrorism".
Jamie Bartlett, author of The Edge of Violence, said it was "understandable" if families of victims of 7/7 were offended, but the film had a "very serious point at the heart of it".
"Many homegrown terrorists are not far removed from the film's characters: incompetent, narcissistic, irreligious.
"It is important that they are seen as such - as it can play a role in denting the brand of al-Qaeda. Satire has long been recognised as a powerful tool to do this," she said.
In January when the film was premiered, Arsher Ali, who plays one of the would-be terrorists, told the BBC the film was first and foremost a comedy.
"It's a dynamic of a bunch of guys who get together and mess everything up.
"Terrorism is in the news almost every day, but there are little stories within those things that are inherently comic and inherently human.
"A film like this is obviously a very strong counterpoint to the very serious side of it, which none of us condone, but there are human stories that need to be told, which can be quite touching."
Last week, many of the relatives' families attended a pre-inquest hearing. The full inquests are due to be held in October.