The final twist in the film was completely breathtaking.

breathtaking 是由动词 breathe（呼吸）和名词 taking（拿取）组成的复合词。字面意思是"夺走呼吸的"，引申为"令人屏息的、极其惊人的"。这里形容电影情节转折令人震惊的程度。