WARNING: This article contains spoilers from Death By Lightning.

Death By Lightning has dropped on Netflix, explaining what really happened to US President James Garfield. The four-part limited series follows two stories: James Garfield's (played by Michael Shannon) time as president and how Charles Guiteau's (Matthew Macfadyen) went on to shoot the president.

Garfield's wife Crete Garfield (Betty Gilpin) had contracted malaria and so had taken some time away from the White House to relax in Monmouth, New Jersey. After dealing with some presidential business, Garfield went to Baltimore and Potomac Railroad Station in Washington DC, in July 1881, so he could travel to see her. Unfortunately, Guiteau had followed him there and fired two shots at the president, one which caught his arm and another through his back.

Death By Lightning revolves around Garfield's assassination so the 20th President did die as a result of the incident on September 19, 1881.

However, the Netflix drama explains that it wasn't actually the gunshot wound which killed Garfield who died two months after being shot.

In the series, a post-mortem is conducted where a mortician removes a bullet as he explains: "Note that the shot migrated left, tucked neatly behind the pancreas.

"It would seem the shot interrupted not one of the president's organs, that the wound healed on its own."

A member of staff asks what it was that could have killed Garfield, to which he replies: "Septic poisoning. Evidenced by the abscesses throughout the body. Infection."

This prompts the staff member to question: "Do you mean he would have recovered naturally if the bullet had been left alone?"

The mortician doesn't say anything but nods as Garfield's physician Dr Willard Bliss mumbles it was a "mistake".

In earlier scenes, Dr Bliss is seen sticking a long metal tool into the wound as blood poured out of the president.

Another doctor in the room questioned if he should be doing this, given the new research in Europe claiming that doctors should be using sterilised equipment.

However, Dr Bliss did not believe this to be "science" and so on numerous occasions, continued to use unsterilised medical equipment.

He was also seen sticking his unwashed hands into the president's wound as he tried to retrieve the bullet, leaving Garfield in agony.

So even though Guiteau pulled the trigger, Dr Bliss had a massive part to play in the death of President James Garfield.

Bliss' professional reputation never recovered from this and he died of a stroke several years later in 1889.

Death By Lightning is available to watch on Netflix.