the men moved a box of stuff into the ship and departed to american halfway through the journey a guy looked in the box and saw the captain was dead!
when they landed the man who found it was arrested
fortunately sherlock holmes and ryunosuke were there, theyd just solved the mysteries of mr brown and the homes and were going home to london and japan but they decided to defend the guy
sherlock looked at the body and concluded he was hit in the head which ryu used to prove it hit hit unconscious from behind meaning the motive was to control the ship so how could the guy be the killer if he wasnt driving the ship at the time? the killer was the man driving the ship but noone knew who did it and there were no fingerprints on the wheel aside from the captains so the killer didnt wipe them off with gloves so they examined the captains room and saw a claw machine
ryu proved that after killing the victim the claw was used as a machine to control the wheel from away from the room and that meant that the killer really could have been the defendant and it was so he confessed
the end