Complex sentence: This is Beatty's and Keaton's first film together since 1981's "Reds," and Beatty's third film with Hawn since 1971's "$" and 1975's "Shampoo".
Split into simpler sentences: This is Beatty's and Keaton's first film together since 1981's "Reds". As well, this is Beatty's third film with Hawn since 1971's "$" and 1975's "Shampoo".