Police are appealing for witnesses and information following a serious injury collision on the A38 between East Huntspill and Pawlett.
Patrolling officers came across the collision at about 10.20pm on Tuesday 7 December. Fire and ambulance crews also attended.
A blue Honda Civic was in collision with the verge after overtaking other vehicles. Soon afterwards a black Vauxhall Astra was in collision with the Honda.
The passenger of the Honda remains in a critical but stable condition in hospital with potentially life-threatening injuries. Their family are aware.
The driver of the Honda was also taken to hospital.
The road was closed overnight for collision investigators to examine the scene and reopened shortly before 7am.
Investigating officers are keen to hear from anyone who saw the collision or the manner in which the Honda and Astra were being driven in the moments beforehand, especially anyone with dashcam or CCTV footage.
If you can help, please call 101 and give the reference 5221287678.