what does "Talk about cutting the tension with a knife,"mean?
“Hi,” she said, in a normal voice. “God. Talk about cutting the tension with a knife, eh? Guy’s always a perfectionist, but this is his first proper shoot since Lula died, so he’s, you know, seriously uptight.”

Question

Answer

We use "Talk about _____!" in colloquial speech to roughly mean "That's a perfect example of ____!"

The idea of cutting tension with a knife means that the tension in the air "was so thick that you could cut it with a knife".  The situation was so tense that you could physically feel it.

Ne manquez pas cette occasion d'apprendre une langue depuis chez vous. Découvrez notre sélection de professeurs de langues expérimentés et inscrivez-vous dès maintenant à votre premier cours !