A new BBC documentary about Cristiano Ronaldo is released on iPlayer on Saturday - and we have taken a deep dive into what to expect.

The film highlights the story of the Portuguese star's upbringing, his time at Manchester United and Real Madrid, his personal development and how he became the world's biggest sporting brand.

It's all told by those who know and have followed his career, including players like Rio Ferdinand, Nani, Lucy Bronze, Gary Lineker and Alan Shearer, plus journalists, coaches and family friends.

Here are just a few things to expect.

Ronaldo: Impossible to Ignore comes to BBC iPlayer on Saturday 29 May and will air on BBC One at 22:20 on Saturday 5 June.
1. Ronaldo didn't have an easy start in life

Ronaldo was the youngest of four children to Jose Dinis Aveiro and Maria Dolores dos Santos Aveiro.

Fernao Barros Sousa, Ronaldo's godfather, talks about the megastar's humble origins: "When Cristiano was born, his parents' finances were in dire straits. Both his parents and his sister were working around the clock, which was hard for him."

His mother emigrated to Paris for work at one point in his childhood and his father was unemployed.

Journalist Edmar Fernandes explains: "Ronaldo loved his father very much, but there were some moments of absence.

"Like so many other people from Madeira and Portugal, he had been recruited to fight in a war and sent to Africa. When he returned, he was no longer the same Dinis. What he encountered in the overseas war ended up causing him depression and he ended up finding refuge in alcohol."

Ronaldo, meanwhile, found refuge in football, training with Portuguese side Nacional from nine years old and then moving to Sporting Lisbon at 12.
2. Sir Alex Ferguson signed him immediately after he embarrassed Manchester United in a friendly

Rio Ferdinand retells the legend of Ronaldo's audition for Manchester United as someone who was there that night.

In the summer of 2003 Manchester United were engaged in a battle with Arsenal to be the dominant force in English football and United had just lost their number seven, David Beckham, to Real Madrid.

They found his replacement in a gawky 18-year-old during a pre-season friendly with Sporting Lisbon.

Ferdinand recalls: "You start hearing whispers, 'they've got this kid called Ronaldo, he's supposed to be pretty good'."

The young winger with braces on his teeth bossed the game.

"He's doing mad stuff, embarrassing a couple of our players," says Ferdinand, "I remember at half-time, I was going to the toilet - I think with Nicky Butt and Paul Scholes and we're all standing there saying 'oh my god, we've got to sign him'."

According to Ferdinand, the team bus was delayed afterwards.

"Noise starts travelling back through the coach that Mr Gill [David Gill, United chief executive at the time] and the manager are in there and they've got Cristiano in a vice-like lock and they ain't leaving until he agrees and signs to come to United. I think that's where the deal was agreed and the rest is history."
3. He used to train alone at Carrington

Mick Clegg was Manchester United's power development coach between 2000 and 2011 and helped Ronaldo transform from a lanky teen into a winning athlete.

"I'm at Carrington and I'm in my chair at the gym," Clegg recalls of first meeting Ronaldo.

"This young lad turns up. He said, 'I've heard about the work you've done. I'm going to be the best player in the world.'"

In another part of the documentary, Clegg describes how Ronaldo used to go off on his own at Manchester United's Carrington training complex to practice behind a concealed hill.

"I asked him about it one time and he said, 'well, there's nobody there, so if I do the skill wrong, nobody's watching me, I can practice it'," remembers Clegg.

Ferdinand concurs that Ronaldo used to practice skills alone before bringing them to training to amaze others with.
4. Alan Shearer is still angry about him getting Wayne Rooney sent off

One of Ronaldo's most controversial moments in the spotlight was at the 2006 World Cup.

England faced Portugal in the quarter-final. In the second half, England's young hope Wayne Rooney was sent off for a stamp on Ricardo Carvalho.

His Manchester United team-mate Ronaldo successfully helped lobby the referee to have him sent off and the cameras then picked him up winking at a Portugal team-mate.

It did not endear Ronaldo to many English fans or journalists. Gary Lineker says the whole thing was probably inflated, but his Match of the Day colleague Shearer isn't so forgiving.

"I still have the same feeling," he says, watching the clip back. "I was pretty angry at the time, so I can imagine how Wayne Rooney felt."

5. He's not happy being second best

Youth coach at Nacional, Pedro Talhinhas, remembers the young Ronaldo "did not have a good relationship with losing" as a child.

It's a trait that's persisted.

Ferdinand describes how he used to play table tennis tournaments with him at Manchester United: "If I won, he wouldn't want to stop. He's not someone who gives up."

He describes Ronaldo's mentality: "The heartbeat of what he does is the team. But he knows what comes with that is the personal honours and he's not ashamed of that."

Ronaldo did not enjoy it then when Barcelona were winning so many trophies between 2009-2013. In that period, Barcelona won La Liga three times, as well as winning the Champions League twice. Nor would Ronaldo have appreciated Lionel Messi pipping him to the Ballon d'Or four years in a row.

Lucy Bronze says though that Ronaldo is her inspiration and describes the difference between the two players: "He's the grafter. For me, getting to the top was about always wanting to be the best. Hating losing, always wanting to win, which is the things that I see in him."

6. He was not satisfied with just winning La Decima

Ronaldo finally achieved his desire to win the Champions League with Real Madrid in 2014 (he had already won the competition with Manchester United in 2008). Paul Clement, who was then assistant coach at Real Madrid, describes the scene in the documentary.

"Playing in the 2014 Champions League final, I'm looking out the tunnel and I can see the Champions League trophy," Clement describes. "When I got that view, it actually physically took my breath away. Cristiano had obviously heard that. He just turned and looked over his shoulder and went, 'Paul, don't worry.'"

Clement also describes how, in the dressing room after Real Madrid had just won La Decima - their tenth Champions League trophy - while everyone else partied, Ronaldo plotted.

"Champagne's popping, the atmosphere's just incredible and then I saw a small group of players - Marcelo, Pepe and Cristiano. I had to ask Cristiano what they're talking about. He said, 'we're talking about how next year we have to come back and win it again.' I thought, wow!"
7. He showed his leadership qualities in the Euro 2016 final

That force of will came to the fore at the Euro 2016 final. Home nation France came in as firm favourites, but they obviously hadn't got the memo that Ronaldo was the protagonist of this story.

After the heartbreak of losing to Greece in the 2004 final, Ronaldo had a score to settle. What's more, as Ferdinand explains in the documentary, there was extra motivation - Messi had never won a major tournament with Argentina.

Not even having to be taken off on a stretcher in the 25th minute would get between Ronaldo and that trophy.

Team-mate Nani describes him barking orders from the side of the pitch.

"He was calling out all the players, every name. He was giving some information. I think almost everyone felt his presence on the touchline," he remembers.

Shearer says: "People at times over the years might have thought he was pretty selfish, in terms of the goals he scored, the desire that he had, but I think when you look at him in that final and the way he was trying to drive his team forward from the touchline, I think that told you how much he wanted to win."