Michael Durrant - the new man in the life of 21-year-old Olivia Davies - believed that Matthew Hutchins owed him money.
So the pair hatched a plot which they hoped would force him to settle the alleged debt, Wolverhampton Crown Court was told.
Mr Hutchins - who split with Davies in March last year but was still fond of her - returned to her Brierley Hill home to deliver some clothes on December 30, said Mr Edward Soulsby, prosecuting.
When he got there he found 31-year-old Durrant was also at the address and left but later while on the bus home in Wednesbury received a phone call from Davies pleading for help because she was in trouble.
He headed back to Brierley Hill arriving after 10pm but while waiting at the end of Bell Street South for his former girlfriend he saw Michael Durrant and ran off towards the Merry Hill Shopping Centre.
Davies, Durrant and Andrew Bradley, a 31-year-old friend of the couple, gave chase in a Jaguar driven by Durrant's brother Mark, aged 29, the court heard.
Mr Hutchins was cornered outside the Odeon cinema where he tried to call police but his phone would not work, continued Mr Soulsby.
Michael Durrant ran at the victim and felled him with a rugby tackle before punching him on the side of the head. He then sat astride the prone figure and 'tried to strangle him,' continued the prosecutor.
The three men and Davies tried to humiliate Mr Hutchins by stripping him in front of startled cinema-goers but only managed to get his shoes off before bundling him into the Jaguar.
The car then drove off with the three men and their kidnap victim, leaving Davies behind outside the Odeon.
Michael Durrant punched Mr Hutchins in the face once more while the three men talked of giving their frightened hostage a good beating but after just a handful of miles the car stopped in Tansey Green Road, Pensnett.
The hostage was pulled out of the car, punched once more in the face by Michael Durrant, told to take the incident as a warning and dumped after the 40-minute ordeal.
He later told police: "I was petrified and the thought of what happened still scares me now. They could have killed me. They said they were going to take me to a field and get rid of me. I worry that after they are released they will come for me again."
Davies admitted making the phone call that lured him and added: "I expected them to treat him roughly to get the money he owed them."
Mr Soulsby concluded: "She set him up."
Michael Durrant from Bodmin Court, Brierley Hill was jailed for two years and three months while Davies, of the same address, was detained for two years.
Mark Durrant. aged 29, of Hilton Road, Tividale and Bradley, from Stourbridge Road, Dudley, both got 20 month prison terms. All pleaded guilty to kidnap.
Recorder Geoffrey Kelly told them: "Davies knew of Mr Hutchins' feelings for her and played on that to lure him to where Michael Durrant was waiting. It must have been absolutely terrifying for the victim."