I actually work as a Blue Badge Guide in London and so was not staying at the Radisson VanderBilt Hotel, but a party of my clients was, and I needed some rather special assistance.
And I certainly got it, efficient and reliable to the end. I had to meet my group there but was flying in from South Africa that same morning. Unfortunately I was a bit late. I had sent an email to the Concierge at the hotel to ask him to manage things for me in the event of my plane coming in late. The name of this Concierge was Darius (from Lithuania originally, I think). He got the group mustered at the Radisson and sent them off to do some London-exploring. When I arrived, he had it all sorted - He got me washed and changed, he took my luggage and had me out of the door in minutes, looking less the weary traveller that I was and more like the Blue Badge Guide that I had to be. He sent me to the right place to meet the group, just in time for the Changing of the Guard - and the rest was easy.
The clients had a great day - and my thanks to Darius for his quiet efficiency in liasing with both me and my group. Great Concierge work.