London's Olympic Ambassadors are back on the streets in a pilot project at St Pancras Station.
The volunteer force will offer advice to visitors on how to get to attractions, restaurants and shopping areas.
But, as Rags Martel reports, they started with something a bit more dramatic.
More top news
Londoners who have received new electronic gadgets for Christmas are being advised to take simple steps to protect them from thieves.
The Boxing Day sales got off to a flying start with shops reporting a surge in business during the first hour of trading.
Bus strikes are planned for Monday 29 December and Monday 5 January.