They had met on the set of John Hughes’ Ferris Bueller’s Day Off, and Grey was just weeks from becoming a household name following her role as Baby in Dirty Dancing.
According to People, the couple had flown to Northern Ireland for a romantic trip after their onscreen appearance as brother and sister in Ferris Bueller’s Day Off, when the pair decided to rent a BMW 316 to drive from Irvinestown to Maguiresbridge.
In the hours before the accident, Broderick, who was then 25, and Grey, who was 27, pulled into a petrol station to ask for directions. After being told their chosen route was "just stupid", an off-duty policeman offered to lead them to the right road.
Broderick declined the offer.
Shortly after, there was a huge downpour of rain, and the Hollywood couple decided to take another break at a petrol station. This time, they found their bearings and waited for the rain to stop.
Less than a mile from the petrol station, 80 miles west of Belfast, they collided head on with a car driven by a 28-year-old woman named Anna Gallagher.
She was driving with her 63-year-old mother, Margaret, and both women were pronounced dead on arrival at Erne Hospital.
The road was reportedly straight and simple, spurring speculation the actor may have begun to drive on the wrong side of the road by habit.
Ken Ramsey, a local fireman on the scene, said the car had to be cut down the side to give Broderick first aid.
Ramsey recalls the actor kept repeating "Did I hurt them? Did I hurt them?", and that while Broderick suffered from a badly broken leg and facial lacerations, resulting in a four week hospital stay in Belfast, Grey only obtained superficial bruising.