A gang of armed robbers held a man hostage for two days at a property in Croydon, stripping him naked and beating him before raiding his parents' Sydenham home.
The 24-year-old, wearing a #9,000 Rolex watch, was lured to a house by two acquaintances while walking down London Road, Croydon, at 2pm on December 4th.
As they approached Langdale Road in Thornton Heath, where a group of knife and gun-wielding attackers lay in wait, he was asked if the gold timepiece was real.
He was then ambushed and subjected to a terrifying kidnap ordeal, which saw him stripped, tied up and threatened with a gun, the Metropolitan Police said.
His 50-hour imprisonment descended into violence, with a kidnapper at one stage booting him in the face, leaving him with badly bruised lips and a lump on his forehead.
The captors then forced the man to ring his parents and make a ransom demand of a "significant sum of money" for his release, which they could not pay.
Instead, two of the gang took his keys and burgled the couple's home on December 6 - their entry captured on CCTV which has now been released by detectives.
Footage shows one suspect, a black man with dark facial hair wearing a high-visibility jacket over a parka, walk to the door and spot the camera.
He returns with an accomplice wearing an orange high-visibility jacket to enter the property, with both men covering their faces.
A significant amount of cash was taken from the home in Sydenham, as well as designer handbags, sunglasses and further Rolex watches, police said.
On the third evening of the hostage ordeal, the victim was taken by car to a branch of the Metro bank in North End, Croydon, so he could withdraw money.
His tormentors waited in the vehicle, apparently out of fear of being captured on CCTV, giving the man an opportunity to escape.
He ran to the Croydon Minster church and begged for help, bringing the traumatic experience to an end as police were called.
Detectives have now released CCTV images and pictures of the "dangerous" men they are hunting.
Two brothers, Ali Dervish, 28, and Sinan Dervish, 19, are wanted in connection with the incident.
Detective Sergeant Samuel Bennett said:
"This was a vicious and prolonged attack of a nature that thankfully is very rare.
"It has left the victim utterly distraught and traumatised.
"We are urgently seeking any information on the individuals involved, who we believe could number up to twelve, but particularly those whose images and details we have released.
"Do you recognise either of the two men shown burgling the house in the CCTV images - or did you see them in Sydenham on the day in question, Wednesday December 6?
"Do you know the whereabouts of Ali or Sinan Dervish?"
Anyone who has been offered a Rolex similar to the one stolen has been urged to come forward.
It is described as a 2007 model with a black face, black bezel and a gold body and strap.
The detective said:
"Any information you have, however small, could prove vital to us as we piece together the events leading up to and following the kidnap. We will treat any information provided in the strictest of confidence.
"These men are dangerous and it is important that we apprehend them before they can target anyone else."
Two men aged 39 and 58 were originally arrested on suspicion of kidnapping on Friday.
They have since been bailed to return to a south London police station in early January.
Anyone with information should call Croydon CID on 101 or tweet @MetCC. Alternatively Crimestoppers can be contacted anonymously on 0800 555 111.