I saw this when I was in Malta, but didn't pick up a copy then since it was published in the 1960s and I thought there might have been a better recounting in the 50 odd years since. However when I was back in England I hunted around and there isn't anything more recent, and having read it I think it would be hard to improve on this account.
The author, as a naval officer, visited the island during the Second World War and so had some idea of what it was like during wartime. He used as one of his sources an eyewitness account by a Spanish soldier at the siege - Francisco Balbi da Correggio, which he later translated for publication. (Most of the sources available are not in English since the English branch of the Catholic Order of St John had been broken up by Henry VIII and so did not take part in the siege, except for one or two individuals.)
Malta was at that time the base of the Knights of St John, who had moved on from their origins as Knights Hospitallers who provided and defended hospitals for crusaders and pilgrims, to becoming religious pirates. Soleyman the First, Sultan of Turkey, who had already driven the Knights from their previous base in Rhodes, decided to remove the threat of the Knights and at the same time gain the stronghold of Malta. Malta has great harbours and if you look at a map of the Mediterranean you can see it's in a very strategic situation, placed between Europe and Africa, and the east and west ends of the inland sea. He sent a large fleet and army (probably at least 3 times the number of the defenders) who landed and launched an attack in May 1565. They were defeated and withdrew in early September.
What is so excellent about this book, is that with simple prose and two sketched maps, the entire procession and locations of the campaign are comprehensively described, so it's possible to follow and grasp all the ebbs and flows of the battles. His style, though simple can also be very expressive. When he describes the Knights' cavalry attack on the Turkish camp, while the main Turkish force was attacking elsewhere, he says: " In the first charge they overwhelmed the sentries. Then the cavalry were among the tents occupied only by the sick, the wounded, and the few slaves who tended them." He could have just written "sick and wounded" but by using the repetitive definite article and mentioning the slaves he makes the subsequent massacre even more real. Although both sides were as brutal as the age accepted as normal, the Christians appear more ruthless - in addition to the above slaughter, they killed prisoners, and drove Moslem slaves to build fortifications under bombardment by their own side. The Maltese population who were the main bulk of the defending forces, had perhaps some excuse for ruthlessness, since they were frequently raided by corsairs, and it had only been 15 years since almost the entire population of nearby Gozo, some 5000 people, had been taken by slavers led by the Moslem corsair Dragut, who was now one of the commanders of the attack.
The Turkish had their own practical cruelty. Soon after they landed they captured a Knight and a Novice of the order, and questioned them. "Chevalier de la Rivière and his companion Faraone had cried out under torture that the weakest point in the defences was the post of Castile." When contemplating arguments for the usefulness of torture (particularly the 24 hour theory) it's worth noting that the post of Castile was actually the strongest point, and the Turkish assault had several hundred casualties.
As in all the Wars of Religion, both sides were convinced of the supremacy of their faith and willing to commit what would otherwise be seen as crimes to support it. In an example of irony, the author notes, "On the lips of the Maltese was also the word 'Alla', for in their language the Christian God was called the same."
Although not so well known nowadays, it was a crucial battle in the history of the Mediterranean and perhaps the world, and the book itself gives not only a vivid account of the siege, but a clear portrayal of the horrors of war.