The footage, seen by Woolwich Crown Court, shows firefighter Angus Campbell holding onto young mother Nadia Baro while remonstrating with Ramzi Mohammed.
The confrontation between Mr Campbell and Mr Mohammed after Mr Mohammed's alleged bomb failed to explode.
Mr Campbell, 43, told the court how Mr Mohammed was screaming and shouting and there was smoke issuing from behind him.
The footage shows Mr Mohammed on the Tube with a rucksack.
Chaotic scenes on the platform as passengers disembark from a tube train, along with Mr Mohammed.
There had been up to 30 passengers on the train when Mr Mohammed eventually left the carriage.
Tube passengers can be seen fleeing from the train and some passengers running in pursuit of Mr Mohammed.
Mr Mohammed can be seen running away on CCTV.