North Yorkshire Police are appealing for witnesses to a serious collision on the A1 between the junctions at Boroughbridge and Dishforth.
The incident occurred on the northbound carriageway at around 7.10am on Saturday October 31.
Three people in the car involved, a dark green Mini Cooper, were all seriously injured when the vehicle left the road and came to rest on its side.
One passenger, a 24-year-old man, was airlifted to James Cook hospital in Middlesbrough where he remains in critical condition.
The driver, a 21-year-old man, and a second passenger, a 20-year-old woman, were both taken to Leeds General Infirmary by road ambulance and also remain in hospital.
The road was closed in both directions whilst the air ambulance landed and the northbound carriageway was closed while emergency services collision investigators attended the scene.
The section of motorway was fully reopened at around 11.15am.
Officers have thanked members of the public who stopped at the scene to provide assistance.
Police are appealing to anyone who saw a dark green Mini travelling north along the A1 before the collision and to anyone who witnessed the crash to contact them.
Anyone with any information is asked to contact North Yorkshire Police on 101, select option 2 and ask for Traffic Constable Rob Roberts at Harrogate Roads Policing Group or email email@example.com