Police are appealing for dash cam footage after a serious crash on the A628 Woodhead Pass.
The collision, near Salter's Brook Bridge, occurred just after 10pm on Wednesday December 12 and involved two cars, a Mercedes E220 and a Ford Fiesta.
Five people in the Fiesta required hospital treatment. One of the passengers, a 66-year-old woman, suffered serious injuries and is receiving treatment at the Northern General Hospital in Sheffield.
The driver of the Mercedes, a 52-year-old man, received hospital treatment for minor injuries and was arrested on suspicion of causing serious injury by dangerous driving.
A Derbyshire police spokesperson said: "Officers investigating the incident are keen to speak to anyone who was in the area at the time, especially those with dash cam footage.
"Any footage that may be of use to officers should be downloaded onto another device and safely kept for officers to view."
Anyone with any information should contact police, quoting the reference number 18000602995 by calling 101 or via the online contact form www.derbyshire.police.uk/Contact-Us.
Alternatively, call Crimestoppers anonymously on 0800 555 111.