The story here is a 777 from Mubai to Heathrow lost communication with ATC, so the Germans sent a pair of fighters to intercept it. They eventually re-established communication. It's pretty weird incident. The pilots would have to have missed several calls for them to switch to the next frequency, then missed a series of calls for them on guard frequency (121.5). Their radios were evidently fine, because when the pilots saw the fighters, they got their act together and tuned 121.5. The weirdness of what's required for persistent loss of communication with an airliner is, I guess, what justifies the cost of sending two fighters to intercept it.
The video is shot by another aircraft, I think British Airways, on the same airway, 2000' feet up. It was great timing.