Why do the officers and crew of the first patrol boat look at the lighthouse with a horrified expression?

The officers and crew of the first patrol boat likely look at the lighthouse with a horrified expression because they have just witnessed something alarming or unsettling, such as a distress signal, an unexpected event, or a dangerous situation unfolding. This could indicate that they are aware of a threat or tragedy occurring nearby, prompting a sense of urgency and fear. Their reaction suggests that whatever they saw has deeply affected them, raising concerns for the safety of those involved.