They went out for fishing.
And caught a lightning!

Four sailors have been found dead and one is missing after a ship sank off of Pini Island, North Sumatra, last week after being struck by a lightning.
The four victims were among seven crew members aboard KM Restu Bundo when the boat began to sink on November 21, 2019 evening.
Three victims were found dead in the waters of Labuhan Hiu, Batu Timur Islands district, South Nias, on Saturday, Nov. 23.
“The three dead victims were very difficult to identify as they had been in the water for a few days,” Sukroadi said on Sunday.
One man of the crew died on Friday after escaping the sinking ship and swimming back to Pini Island. After reaching the shore, he died from his severe lightning burns. Two other crewmen who swam with survived the accident.
One crew member is still missing. But I think it will pretty hard to find him alive
According to officials, KM Restu Bundo departed on Sunday, Nov. 17, from Sibolga city in North Sumatra to fish the waters around Pini Island. The ship was struck by a lightning on Nov. 21. [The Jakarta Post]