A passer-by punched a drug-driver and held him down until police arrived after he knocked a cyclist off his bike and attempted to flee the scene.
John Sinclair's vehicle was so badly damaged his attempts to drive away after the crash failed.
Armed with a knife, he tried to stop and enter cars driving past. He eventually approached one containing a dad and his eleven-year-old son who he told he had a gun before clambering on top of the child.
The terrified father and son were rescued as a passer-by punched Sinclair and dragged him out of the vehicle, pinning him down until police arrived to arrest him.
The 39-year-old, from South Shields, Northumbria, was jailed for 30 months after admitting a series of offences at Newcastle Crown Court last Friday.
The court heard the crash took place in South Shields on 29 September last year when Sinclair took his mother's Toyota Aygo on a high-speed joyride without her consent.
Read More From Yahoo News UK:
Witnesses estimated Sinclair was doing up to 80mph before colliding with a cyclist, knocking him off. He then collided with another car with force, causing it and his car to spin out of control.
In an effort to escape when he could not start the damaged car, Sinclair produced a hunting knife and began trying to get into passing cars.
He approached the father and son's car, repeatedly saying "I've got a gun".
Prosecutor Kevin Wardlaw told the court: "He opened the passenger door and dived into the car on top of the eleven-year-old son in the front passenger seat. The man said he believed his son would be injured. He was trapped under the defendant.
"He was concerned for the safety of his son and felt physically sick."
After being arrested Sinclair admitted taking cocaine and heroin beforehand and said he had pressed the accelerator instead of the brake pedal.
Detective Chief Inspector Sean Mcguigan, of Northumbria Police, said: “This could so easily have been a very different outcome. Sinclair’s erratic and dangerous actions led to him knocking a cyclist off his bike at high speed, before crashing into a car on a busy road. He was under the influence of drugs, and could easily have killed somebody.
“Immediately after the collision, armed with a knife, he then left motorists terrified as he tried to get into other vehicles in a desperate bid for freedom.
“Thankfully, nobody was injured – and that is largely due to the extraordinary actions of this Good Samaritan.
“We would always discourage the public from risking their own safety, but it’s important to recognise examples of bravery such as this.
“It is because of their bravery and cooperation that effective justice has been served, and Sinclair now begins a rightful jail term.”
Sinclair, who has 18 previous convictions, including violent offences, pleaded guilty to dangerous driving, aggravated vehicle taking, affray, possessing a blade and having no insurance.
Chris Knox, defending, said: "At the heart of his behaviour is drugs. He was acting out of character."
The court heard he was a "skilled advanced paint technician" with good job prospects.
Watch: What are Incels and Femcels?