Given the task definition and input, reply with output. Given a sentence and two mentions from the text (arguments), indicate a phrase (a verb or noun phrase) that describes the relationship between the provided arguments.

Sentence: 'Christian Bale , star of Dark Knight , and the upcoming Terminator Salvation film was recorded on set lambasting his director of photography , Shane Hurlburt for his lack of professionalism .', Argument/Subject 1: 'christian bale', Argument/Subject 2: 'dark knight'
star in