Zero Day ending explained: Who was behind the cyber attack?

Robert De Niro's ex-president character George Mullen is brought in to head a commission, hoping to find the culprit and their motives.

But if you've seen all six episodes, or simply want to know how it all plays out, what did he uncover, who was behind the attack and what happened to George at the end of the season?

Read on for everything you need to know about the ending of Zero Day on Netflix.

Zero Day ending explained: Who was behind the cyber attack?

It turned out that the Zero Day attack was part of a wide-ranging, cross-part conspiracy, led by House speaker Richard Dreyer and also including George Mullen's own daughter, Congresswoman Alexandra Mullen.

Others involved included Congressman Jerry Benson, Congresswoman Barbara Rollins, Senator Max Trillin and Senator Pat Bishop, while those outside of the political sphere also played central roles, including billionaire Robert Lyndon and tech entrepreneur Monica Kidder.

The Cyber weapon they used was devised by the US' National Security Agency, and the plan was for a short attack in which no casualties were intended.

People around the US would be spooked by the attack, realise their collective vulnerability, and rally around the centre, bringing in a new era of bipartisanship and ending the country's extensive divisions.

Dreyer was hoping that he would be put in charge of the commission rather than George, giving him all of its power. He had promised Alexandra that this would allow him to remove the far-right elements of his party, and then he would work with her on bipartisan legislation.

Did George Mullen reveal the truth?

A number of different parties tried to convince George not to reveal the truth, including President Mitchell, who suggested the amount of corruption this would reveal could bring the whole governmental system crashing down.

Dreyer said he would step down at the end of his term and convince the other conspirators to do the same. George seemed to be going along with this, planning to just implicated Kidder and Lyndon, with the former incarcerated and the latter having fled the country.

However, in the end, while making his speech to congress, George revealed the truth, to the shock of the room and America at large. He even revealed Alexandra's involvement, and said that the investigation would need to continue to root out more of those who were involved at lower levels.

What did we learn about George's past and was he being targeted?

Throughout the series, George suffered apparent hallucinations, seeing visions of a journalist who had died after offering to help him with his memoirs, as well as ones of his son Nick, who had died during his presidency.

He also heard music and saw blurred visions, and suffered from apparent paranoid delusions. At one point, it was suggested he could be being targeted by a chemical weapon, Proteus, which, when used, can cause these symptoms.

In the end, Valerie investigated the apparent source that could have been used to administer Proteus, but it was impossible to determine its origins. It was suggested Proteus could have been used on George, or it could have simply been his raddled and guilty mind playing tricks on him.

We also found out another of George's secrets during the series - not only did he have an affair with his chief of staff, Valerie, but he also fathered a child with her.

Part of his reason for standing down after his first term, it is suggested, was to stop that secret from coming out, sparing Valerie and the child from a lifetime of media scrutiny.

Zero Day is available to stream on Netflix now. Sign up for Netflix from £4.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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