The Royal Melbourne's doctors Scott Taylor and Jonathan Papson attend a pregnant woman, badly injured in a high-speed traffic crash.

Doctor Glenn Harrison fears a tradie, crushed under 300 kilos of cement, has brain injuries. Drs Mya Cubitt and Jana Alexander diagnose a 'healthy' man with a ticking time bomb.

Dr Mark Putland and the Royal Melbourne Hospital trauma team have minutes to save a truck driver's severed leg. Nurse Chelsea Jones fears a horse rider might be paralysed.

Doctors Jonathan Papson and Emmanuel Karpathakis fear a cyclist with glass sticking out of his neck could bleed out. Any movement could be catastrophic.

Dr Terry Kane faces the worst trauma he's dealt with. A motorcyclist has a broken pelvis and could bleed to death. Nurse Chelsea Jones fears his forgetfulness could be a brain bleed.

Doctors worry a mechanic could lose his crushed arm. Dr Luke's decision not to ride a bike in the city is reinforced when treating a cyclist after being hit by a car.

Dr Andrew Trezise worries a young dirt bike rider has life-altering injuries after a crash. Dr Jonathan Papson fears for a showjumper with multiple breaks after being thrown off a horse.

Dr Jonathan Papson discovers devastating news for an injured driver. Drs Andrew Wallace and Emma West fear a chef, who fell down an escalator, has brain injuries.

Dr Jonathan Papson is impressed with the pain tolerance of a mechanic who was crushed under a two-tonne ute, after the jack gave way.