Paul Walker died in a devastating car crash on Saturday November 30th in Santa Clarita, Calif.

The Porsche GT, which crashed into a tree then a lamppost before being engulfed in flames, also killed Walker's friend, Roger Rodas, who was behind the wheel at the time of the accident.

In the 'Fast & Furious' star's autopsy report it was determined the cause of death was from "combined effects of traumatic and thermal injuries."

But since the crash the question still remains, what caused it to happen?

Stunt experts have come up with what they believe is a solid theory into the cause of the accident, the car may have hydroplaned when hitting road bumps at high speed, according to TMZ.

This theory, which was told to the Walker family, suggest that when a car travelling at speeds of 90mph hits the plastic bumps, known as Botts' Dots, it will lose friction, similar to driving on ice.

That model of Porsche Paul was in is fitted with sports racing tires that have very little grip to begin with, thus the car would be near impossible to establish control again.

Paul's family reportedly believe this is what caused the fatal crash.

Although the theory is possible, Law enforcer's told the gossip site that they still haven't determined the cause of the accident but they are considering it as a potential explanation.

The investigation into the cause of the crash doesn't seem to be stopping anytime soon but Walker's remains have already been returned to his family and they are undergoing the funeral arrangements.

Only family and close friends will be attending the service, including the 'Fast & Furious' cast.

Paul Walker
Paul Walker was 40 years-old