Police have released fresh CCTV of the two Russians suspected of poisoning Sergei and Yulia Skripal with novichok.
The footage, which has not been seen before, shows the pair as they travelled around Salisbury on 4 March before the former Russian spy and his daughter were found slumped on a bench.
Images of a specially made model of the counterfeit perfume Nina Ricci bottle which contained the nerve agent has also been released in the hope of hearing from people who may have seen it at the time.
The fresh appeal comes as the police officer who was poisoned with novichok after the attack on the Skripals told how he was "petrified" and the effect has been an "emotional battering".
Detective Sergeant Nick Bailey was poisoned after touching the front door handle – where the chemical was sprayed – of the Skripals' house in Salisbury as he and two colleagues searched it on the night of the attack.
Despite wearing a hazmat suit, the 38-year-old father started to feel unwell shortly after.
"My pupils were like pin pricks. And I was quite sweaty and hot. At that time I put it down to being tired and stressed," he told BBC's Panorama.
He said he tried to sleep it off but two days later he felt even worse so his family rushed him to hospital.
"Everything was juddering, I was very unsteady on my feet," he said.
"The sweating had gone from my forehead down my back. My whole body was dripping with sweat."
The police officer remained conscious throughout his ordeal, while the Skripals – one of whom was in the next door room to his under police guard – were in comas in Salisbury District Hospital.
He said he was "petrified" when medics told him blood tests had revealed he had the deadly nerve agent novichok in his system – a word most people were thankfully not familiar with at the time.
"I didn't understand how it had happened, scared because it's the fear of the unknown because it's such a dangerous thing to have in your system," he said.
"Knowing how the other two [Yulia and Sergei Skripal] were or how badly they'd been affected by it, I was petrified."
Det Sgt Bailey said it was painful "at the beginning" when he would have "five or six infusions" in his arms at a time.
Fifteen days after the attack, investigators discovered the Skripals and Det Sgt Bailey had come into contact with the novichok by touching the front door handle.
The police officer said: "I don't know whether, if it's gone through the gloves, I don't know whether, I mean, I could have adjusted my face mask and my goggles whilst I was in the house with it being on my hand.
"It's such an outrageous, dangerous way of doing something that it angered me as well because any number of people could have been affected by that."
Det Sgt Bailey was released from hospital after two-and-a-half weeks but he could not go home as his family can no longer live in their house due to the contamination.
Everything the Baileys owned had to go, including their cars, all the children's toys, and all their possessions.
He said he "bounced back pretty well" physically, but emotionally "that's a different kettle of fish".
"That's taken longer," he said.
"I describe it as emotional battering and psychological impact. It's taken longer to deal with just because of everything that has happened to us.
"We lost everything. And yeah it's been very difficult to kind of come to terms with that."
Three months after the attack, Salisbury resident Charlie Rowley found the Nina Ricci perfume bottle and gave it to his partner Dawn Sturgess, who sprayed it on herself.
The pair did not realise it actually contained novichok – enough to "kill thousands" – and Ms Sturgess died nine days later while Mr Rowley survived, having only got a bit on his hands before washing it off.
Det Sgt Bailey said: "I was in absolute shock when I heard about what happened to these two people and my heart goes out to Dawn and her family because I was able to walk out of hospital and sadly she wasn't."
Her death helped detectives solve the puzzle of where the novichok had gone.
For Det Sgt Bailey, he has to live with the effects and said he is taking "each day as it comes", with the public reaction "overwhelming" – he said he wishes he could "thank everybody".
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After being released from hospital, the Skripals were taken to a safe house where it is assumed they remain – under protection of the British government.
The investigation into the Salisbury attack continues, with the lead detective, Deputy Assistant Commissioner Dean Haydon, saying he "will not give up" until those responsible are brought to justice.