Commotion on the Ocean (1956)

The stooges are would-be reporters, who are tricked into becoming stowaways by "Borscht", a spy for an enemy country. Stranded on a freighter on the high seas, they discover that Borscht has concealed some stolen microfilm in watermelons they brought aboard for him. After a wild chase, they subdue Borscht and recover the microfilm.