Fergie quits, dressing room feuds and the Arsenal bible - what we learn from Man United Treble documentary

It might be 25 years ago but Manchester United's historic Treble in 1999 remains a story that captivates and a new documentary released on Friday has retold that season.

The three-part Amazon Prime documentary includes contributions from some of the key protagonists that season and reflects on a tricky start to the campaign, a stunning unbeaten run and a famous finish in the Nou Camp.

It also tells some of the key stories from the season, such as Peter Schmeichel's decision to retire, Sir Alex Ferguson's threat to quit and the strike partnership that developed between Andy Cole and Dwight Yorke.

You can watch the documentary on Amazon Prime from Friday, May 17 and these are some of the biggest takeaways from the retelling of the most famous season in United's history.

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Fergie shock

The look on Gary Neville's face when he's asked whether he knew the manager had resigned in the summer before the Treble season says it all. It was the first he had heard of it.

The story is recounted in Matt Dickinson's book on the season, which is partly what this documentary is based on, and Martin Edwards retells the dramatic tale on film here.

“We felt maybe that he got more interested in outside interest than perhaps he should have done and that just needed addressing," said Edwards. Ferguson's response was to resign, which Edwards accepted before the Scot had a quick change of heart.

Arsenal rivalry

In interviews to publicise the documentary Gary Neville said one of the things forgotten about that season was how good a side Arsenal were and while