A woman was left with a fractured skull after she was attacked with a high-heeled shoe following a night out in Coventry.
The incident happened in Coventry city centre on October 2 and is believed to have followed an argument over a taxi.
West Midlands Police have released CCTV footage of a woman detectives want to speak to in connection with the attack near the junction with Bishop Street and Corporation Street.
Detective Constable Phil Swann said: "The image was captured inside a nightclub on the evening prior to the assault. If anyone believes they recognise this woman I'd ask them to contact me.
"This was a nasty assault and one which could have had tragic consequences. The victim now has a scar on the side of her head but thankfully she didn't suffer any permanent brain injury."
The offender is described as a black woman in her 20s, no taller than 5ft 4ins.
Police said she had black hair and was wearing a short dress with a faint leopard print.
Anyone with information about the attack is urged to contact detectives at Willenhall Police Station on 02476 539816.