The three novels in what became known as The Merlin Trilogy – The Crystal Cave (1970), The Hollow Hills (1973), and The Last Enchantment (1979), were later added to forming a five-book series. The latter two were ‘The Wicked Day (1983)’ and ‘The Prince and the Pilgrim (1995)’. From the 1960s through to the 1980s, Stewart’s Merlin books were very popular, a success following on from the publication of T. H. White’s ‘The Once and Future King’ and also from the US presidency connection with Camelot under John F. Kennedy. In later years, her novels were again reprinted and there was a resurgence in her popularity as an Arthurian tales author.
Mary Stewart has also written many books in the romantic suspense subgenre. For more information please go to Wikipedia: Mary_Stewart.