Detectives hunting a rapist have released "disturbing" CCTV footage of a 24-year-old woman being carried off by the man before the attack.
The victim was walking to get a taxi home after a night out in Leeds when she was approached by the man, who picked her up in his arms and carried her away.
West Yorkshire Police said the "traumatised" woman agreed for the footage to be released in the hope that her attacker would be identified and arrested.
Detectives said they "strongly believe" other CCTV clips, from the night of the attack in August, show the man searching for someone to attack before focusing on the victim.
The man approached the victim and walked with her before picking her up and taking her to the scene of the attack in Mark Lane, next to the St John's shopping centre, shortly after 5am on August 14.
The footage shows him walking around Leeds city centre prior to the attack and police want to trace a woman he approached in Swinegate at about 4.45am.
They would also like to speak to a man seen walking in the opposite direction to the attacker when he approached this woman and the driver of a taxi parked nearby.
Police said the man - who is described as black, aged 30 to 40 years old, taller than average and with a shaved head - could be a doorman, as he was dressed smartly in a long, black overcoat and black trousers.
Detective Superintendent Pat Twiggs, of West Yorkshire Police, said: "The footage of the victim being carried off by this man clearly makes for disturbing viewing.
"We gave very careful consideration to releasing it and secured the consent of the victim who has been left understandably traumatised by what this man did to her.
"I think the CCTV gives a really stark illustration of the very serious nature of this offence and we hope it will focus the public's minds on helping us to identify and trace the man responsible.
"The other footage we have released shows this man walking around Leeds city centre and we strongly believe he has been looking for someone to attack before he focuses on the victim."
Mr Twiggs added: " The circumstances of the offence and this man's behaviour leading up to it are a serious cause for concern and we need to identify and arrest him at the earliest opportunity."
Police appealed for anyone with information to contact Detective Constable Rachel Gilsenan on 101 or Crimestoppers anonymously on 0800 555111.