New CCTV of the July 7 bombers calmly planning and embarking on their suicide mission has been played at the inquests into their victims' deaths.
The grainy and jerky footage shows the four men buying supplies, carrying out a reconnaissance trip to London and then setting out on their final journey.
A police expert said they appeared not to care about being caught on video and acted "completely natural" as they finished their preparations for the deadly attacks.
Scotland Yard launched a massive trawl of thousands of hours of CCTV images after the 2005 bombings on London's transport network, which left 52 innocent people dead and more than 700 injured.
Four days later a police officer with a military background spotted the bombers in footage taken on July 7. They were wearing large rucksacks and walking two-by-two through King's Cross station in central London.
Detectives narrowed down their search and found video evidence that the men had together boarded a train from Luton bound for the capital.
Clips played to the inquests showed Jermaine Lindsay, 19, arriving at Luton railway station just after 5am and fellow bombers Mohammed Sidique Khan, 30, Shehzad Tanweer, 22, and Hasib Hussain, 18, parking alongside him two hours later.
The blurry black-and-white images, captured from a distance in a steady drizzle, then depict the four men putting on the heavy rucksacks packed with home-made explosives.
Appearing overdressed in heavy coats compared to other travellers, they walk into the station in pairs and board the 7.25am service to King's Cross Thameslink.
Arriving in the capital, they transfer to the Underground, following close behind a little girl in a pink coat hand-in-hand with her mother.