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Description - Let's get to know Madeleine. She had blonde hair, blue-green eyes, and a dark strip on the iris of her right eye. She was three years old at the time of her disappearance.

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The McCanns - Her parents, Gerry and Kate McCann, worked as physicians. Maddie was born in 2003, and they had twins in 2005.

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Spring break - On April 28, 2007, the McCanns started their spring break at Praia da Luz, a resort in the Algarve region of Portugal.

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5A - The McCanns stayed at 5A, Rua Dr Agostinho da Silva. 5A was a ground-floor apartment with two public entrances, one in the front and one in the back.

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The Tapas Seven - They were on holiday with seven friends, known as the "Tapas Seven," who had eight children between them. The Seven dined at 8:30 pm at the resort's tapas restaurant.

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Abandoned children - The Seven had booked their table for the last night of the holiday. The parents left the children in the apartments, which weren't far from the restaurant.

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Gerry goes to check - At around 9:05 pm, Gerry checked on his children in 5A. They were sleeping in a bedroom next to the front door. Madeleine slept by the door, and the twins were in the middle of the room. No problem, apart from the fact that the door was wider open than he remembered.

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The Tanner sighting - Ten minutes later, Jane Tanner (one of the Seven) apparently saw a man carrying a child. This would be called the "Tanner sighting."

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False lead - This gave a time frame for the investigation, but it was found that the man was simply another tourist returning home from the Ocean Club that night.

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Maddie's missing - At 9:30 pm, Tapas Seven member Matthew Oldfield offered to check on 5A, but didn't get a proper look inside the room. Kate checked at 10:00 pm, and found Madeleine missing.

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"Someone's taken her" - Kate ran back to the Tapas Seven, apparently yelling "Madeleine's gone! Someone's taken her!"

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Alerting the Portuguese police - All ranks of Portuguese police were notified by midnight. Sixty staff and guests searched until 4:30 am.

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Another lead - At 10:00 pm, the same time Kate reported her daughter missing, tourists Martin and Mary Smith apparently saw an uncomfortable-looking man carrying a young blonde girl 500 yards (460 m) from 5A. Police focused on this after the Tanner sighting was dismissed.

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Mistakes made in the golden hours - There were many mistakes made in the "golden hours" after the disappearance, and the McCanns clashed with the Portuguese police throughout the case.

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Police blunders - Among other things, border and marine police were not properly notified for hours. There were no house-to-house searches, or even roadblocks (Kate claimed).

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Missed opportunities - What's more, motorway CCTV wasn't requested, and the roads were not appropriately monitored. It took Interpol five days to issue a worldwide missing-persons alert.

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Tampered crime scene - Many people in the resort weren't interviewed, and the crime scene was not properly secured. Forensics from 5A were sent to three different labs, and around 20 people had walked through 5A before it was closed off.

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Crime scene rented out - Police reports show that 5A was empty for a month after Maddie disappeared, and was then rented out to tourists until tests continued in 2007.

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Media attention - The news spread, with this becoming "the most heavily reported missing-person case in modern history," according to the Daily Telegraph.

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Suspects? - The media circus arguably made things worse for police, who were apparently suspicious of the McCanns from the start.

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Marketing Maddie - The McCanns have been criticized for how they have "marketed" Maddie's disappearance. Speaking with Vanity Fair, Gerry said this was to keep his daughter in the public eye.

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Unprecedented attention - The McCanns set up a PR team and a fund to raise money and awareness. Due to the rise of Twitter and social media, the case received unprecedented attention around the world.

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Robert Murat - 12 days after Maddie disappeared, Robert Murat (a British-Portuguese man) became the first "arguido" (formal suspect). He stayed 150 yards (137 m) from 5A, in the same direction the "Tanner sighting" man was walking.

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Cleared - Murat was apparently spotted by several witnesses, and he was thoroughly investigated on May 15. However, he was cleared of suspicion in 2008.

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Car rental - The McCanns hired a Renault Scenic car on May 27. Sniffer dogs reportedly reacted inside of the car, potentially implying Madeleine had been inside. On June 6, the McCanns were asked about their involvement by a German journalist.

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Sol accuses the McCanns - Sol, a Portuguese newspaper, published a critical piece on the McCanns later that month. Among other things, the article pointed out alleged inconsistencies in their account of the night Maddie disappeared. 

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Police build suspicion - In July 2007, police started to suspect that there was no abduction, and that Madeleine had died in the apartment.

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McCanns return to the UK - DNA tests from the car were inconclusive, but the McCanns were made "arguidos" on September 7. They returned to the UK two days later.

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Gonçalo Amaral - Since then, not too much has happened. Chief Inspector Gonçalo Amaral (pictured) left the case months after the McCanns left Portugal, before publishing a book accusing them of foul play. The Portuguese Attorney General closed the case on July 21, 2008.

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£11.75 million for a missing person -

Since then, the UK has been handling the search. There's been several inquiries and leads, but nothing conclusive. As of 2018, the total cost of the inquiry is £11.75 million. The McCanns are no longer suspects in Portugal, and are presumed innocent in the UK.

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