10 Hidden Details You Completely Missed In Outstanding Biopics

A great deal of effort and gruelling training went into making the fight scenes in Raging Bull (1980) as brutal and hard-hitting as possible. Robert De Niro sparred roughly around 1,000 rounds to get into the physical shape necessary to play a young Jake La Motta... with the actual fighter himself! He also took part in three legit boxing matches and won two of them.

However, training alone wouldn't be enough to bring the more vicious moments in the ring to life. If we were to truly believe a fighter was being beaten to a pulp, we'd need to see a bit of blood.

Yet, where most directors would usually opt for the typical corn syrup mixture we've grown used to seeing on screen, Martin Scorsese had chosen to make La Motta's biopic a black and white feature. This meant he'd have to resort to another method.

This involved using Hershey's Chocolate sauce as a blood substitute throughout filming as the texture came across as more convincing in black and white than the usual fake blood mixture.

It ended up working a treat. Even when you realise you're watching De Niro get hit in the face whilst coated in delicious chocolate sauce, the scenes still feel as intense and savage as they did prior to learning about this sugary secret.