Investigators are appealing for witnesses to a fatal accident on Horton bypass on the A303 near Ilminster.
The accident happened at 4.30pm on Bank Holiday Monday and involved three vehicles. Police believe that an eastbound Renault Laguna hit a road sign and fencing before ending up on the other side of the road, colliding with a westbound VW Golf.
A Ford Focus, also westbound, was hit by debris as it passed the scene. The driver of the Laguna died as a result of the accident. He has been identified as 26-year-old Grzegorz Sudinor from Croydon, Surrey.
Anyone with information is asked to call Crimestoppers on 0800 555111.