The Telangana police investigates a bizarre murder case in which a pair of lovers have been accused of allegedly killing the woman's husband and then sought cosmetic surgery so the male lover could take his place.

M Swati, a 27-year-old nurse at a private hospital in Nagarkurnool town, had been married to Sudhakar Reddy, 32, for three years and they also had two children, reports NDTV.

The police say she had an affair with Rajesh, a physiotherapist, and they made a plan to kill her husband and also get his property.

On November 27, they allegedly injected anaesthesia into Mr Reddy and when he fell unconscious, hit him on his head, killing him. They allegedly dumped and burnt the body in the forests.

Swati allegedly poured acid on her lover's face and told her family that her husband had been attacked by unknown people. The plan was for Rajesh to have plastic surgery and pretend to be her husband.

Rajesh was being treated in hospital and for a while, the two believed they could pull off their plot, reports NDTV.

The police say Mr Reddy's relatives grew suspicious when Rajesh refused to have mutton soup served to patients with burn injuries. They were shocked when he told the hospital staff that he is vegetarian. Swati's husband was non-vegetarian.

Then the family noticed more differences in Rajesh's behaviour and reportedly started testing him by asking him to identify relatives. Unable to answer the questions, Rajesh allegedly stopped speaking and started communicating with signs.

Mr Reddy's family informed the police. When the police interrogated Swati, she allegedly confessed to killing her husband with Rajesh's help.

Swati was arrested on Sunday. The police say she told them she was inspired by a 2014 Telugu movie. In the movie, a young man is wounded and a woman plastic surgeon gives him the face of her dead son.

A police officer said Rajesh will be arrested after he is discharged from the hospital.