Keeley Hawes broke down in tears as she told of the huge burden of playing the policewoman who fought for justice for "honour killing" victim Banaz Mahmod.
Banaz, 20, was raped and strangled on the orders of her father and other family members after ending her abusive arranged marriage and choosing her own boyfriend.
She was failed by police, having asked for protection multiple times, even naming her would-be murderers.
The Londoner was killed in 2006 and her body was found in a suitcase buried in a garden in Birmingham.
In ITV drama Honour, Keeley plays DCI Goode, who led the inquiry, and said she felt more pressure than she'd experienced in any other role.
"We were so mindful we were dealing with real people, so there is that element – much more so than anything I've worked on.
"The responsibility is huge, I felt it every day, every day since."
Weeping, she added: "You want to do the right thing by everyone and to give Banaz the utmost respect, and also do the right thing by Caroline.
"It's unimaginable what Banaz and her family have been through. Caroline dedicated her life to this case."
Mum-of-three Keeley, 44, admitted she felt ashamed at knowing little about honour killings beforehand and she "went through every emotion" while reading scripts.
And the Line of Duty star has huge respect for "extraordinary" DCI Goode and her desire to achieve justice, after seeing a documentary about the case.
Writer Gwyneth Hughes said the ITV two-parter, which airs later this month, was a really important story.
She said: "Banaz wasn't any kind of doormat – she was a shy, homely girl but had the courage to attempt to tell police what was happening to her."
Praising DCI Goode's efforts she said: "The upshot was five life sentences for murder, which doesn't bring Banaz back any more than our film can.
"But we are all here to honour her in the proper use of that word."
