An exercise in nostalgia. The cast did a great job of mimicking famous people from the past. If you want to see Elizabeth Taylor watch her in one of her movies.
The interplay between Guilgud and Burton was the best bit. Again two very good actors playing other actors but the battle-ground between enfant terrible and experienced thesp gave good theatre. The conclusion, that the old guard informs the new but also makes way, is rather formulaic. And the last scene and use of music buttock-clenching.