Complex sentence: But then, looking around at each other, they knew they had it; so, bleary-eyed and still laughing they settled in to work out the details of the terrifying sequence that would become famous.
Split into simpler sentences: But then, looking around at each other, they knew they had it. So, bleary-eyed and still laughing, they settled in to work out the details of the terrifying sequence that would become famous.