My question is about the situation where there's say a film which is poorly made and would leave a bad impression overall, were it not for the exceptionally good performance of one sole actor which compensates for all the other shortcomings.
One could say that that particular actor had saved what would have otherwise been a completely unsatisfactory production.
I'm looking for the correct phrase to express this. Please note that I am only using film as an example. In my native language, the same expression that can be applied to a good actor that makes an otherwise bad film bearable can be applied to any 'anomalously high-performing' element that 'compensates' for all the substandard elements in an ensemble.