In the novel The Floating Admiral, Arthur Holland is the fiancé, and later husband, of Elma Fitzgerald.
Arthur is described as being very tall, "six foot three at the very least". He has the build and gait of an athlete who specialises in "events requiring exceptional strength". His shoulders are "magnificently broad", and he has a handsome head, "with sunburned face and neck". He has a square chin, and a "short aquiline nose". His hair is brown and naturally curly, but he wears it cropped close. His eyes are hazel, and they are big and fiery.
According to Mrs Emery, Arthur would follow anything Elma said "like a lamb with a blue ribbon round its neck".
Arthur is thirty-three years old, and has no permanent address. At the time of the events of the novel, he is staying at the Lord Marshall hotel in Whynmouth.
Arthur comes to Rundel Croft on the morning after Admiral Penistone's death, looking for Elma. He is determined to enter the house, although the butler, Emery, tells him that the Inspector said that no one was to be allowed in.
Arthur tells Inspector Rudge that he is a trader, trading in raw materials, such as rubber, jute, and ivory. He says that he is currently in London fixing up markets, which may be anywhere in the world. At first he says that he sources his materials from wherever he thinks "the goings good at the moment", but after the Inspector says that it would not be difficult to find out and it would be better to tell him, he admits that he sources his materials from China.
After some investigations conducted by Sergeant Appleton, it is found that Arthur is known all over the East and in London as "the very best type of trading Englishman". He is known to be "energetic, determined, dead honest and reliable", and it is not necessary to get his word in writing, because he performs whatever he promises, and does so "just a shade better than anyone else".
On the night of the murder, Arthur had arrived in Whynmouth by the express train from London. He knew that Elma was dining out, so he stayed in Whynmouth, and went to bed early. However, according to Mrs Emery, he telephoned to Rundel Croft, wanting to see the Admiral. When she told him that the Admiral would likely be out until late, he said that he might come to the house later.
Arthur goes to London to look for Elma, and later marries her by special license. After they return from London, he explains to Inspector Rudge that he had seen the Admiral alive in his study at a quarter past twelve the night before, and had been given written consent to marry Elma. He tells the Inspector that he had not mentioned this earlier because he was afraid that the Inspector would stop them from going to London.
Arthur later goes to the vicarage with Elma, and they discover the body of Célie Blanc. He tells Inspector Rudge that they had heard Célie fall, and he had held her up for a second, but had not disturbed her hands or the knife because he thought she was dead.
It is later revealed that Arthur had met Walter Fitzgerald in the East, and they had become friends. There was a charge against Walter for forgery, which prevented him from claiming his inheritance. Arthur had promised to see what he could do, and interviewed the firm in Hong Kong. However, as Walter could not repay the money he owed the firm, Arthur tried to get in touch with Admiral Penistone in England, to try and bring about a reconciliation, so that the family could advance some money to Walter.
Arthur fell in love with Elma, but was received with suspicion by the Admiral, because he was a friend of Walter. He eventually managed to improve his standing with the Admiral, but still could not obtain his consent for him to marry Elma.
At the end of the novel, Arthur and Elma drive away with Walter.