Emergency services were called to Tower Hill Road, in a logging area at Bright, about 1am on Thursday.

The driver of the vehicle had lost control of his Subaru at the top of a hill and rolled about 100 metres.

Three people were ejected from the car.

The driver was stuck in the vehicle and had to be removed by SES volunteers after one the occupants raised the alarm.

Debris, including car parts and items from inside the vehicle, was strewn down the hill.

The green four-wheel-drive was extensively damaged.

SES deputy controller Graham Gales said he was amazed the other occupants weren't more seriously injured.

The driver, 20, suffered head injuries in the crash and was flown to the Royal Melbourne Hospital in a critical condition.

He was in a serious condition on Thursday afternoon.

A female passenger, 20, was also flown to the hospital in a critical condition with pelvis, leg and spinal injuries

She had improved to a stable condition.

A man and woman, both 19, were taken to Wangaratta hospital with non-life threatening injuries.

It was unclear if alcohol was a factor in the crash, but there were beer bottles inside the damaged car and on the hill.

Mr Gales said volunteers had to remove the roof of the damaged vehicle and take the driver out through the back of the car.

"Given the fact they were ejected and it rolled down the hill, it was surprising the injuries weren't more serious," he said.

"It was impressive the way the emergency services all worked together.

"Everybody knew their role and contributed, and stood up when assistance was needed."

About 25 emergency workers attended the scene, which is located near the Tower Hill Lookout.

Police are investigating the cause of the crash.

"Police are currently investigating the circumstances surrounding the crash and are keen to speak to any witnesses," Leading Senior Constable Melissa Seach said.

Anyone with information about the incident can contact 1800 333 000.