This is the novelisation of the four part story first broadcast in 1980, as the first story of Season 18, and the first story produced by John Nathan-Turner. The novel itself is written by the writer of the story, which is good as it means the novel should really reflect the writer's original intentions. I found this on tv a confusing and rather muddly story; in the novel, it at least has the opportunity to explain elements that don't come across on the visual medium, so it's less confusing. But I'm afraid I still find it rather muddly.
The Doctor and Romana, with K-9 are taking a holiday on Brighton; or they are, until K-9 swallows too much seawater and blows a few gaskets, and the weather on Brighton is not suitable for a beach holiday, so Romana makes the Doctor take them to Argolis, the Leisure Planet. Here, if anywhere in the universe, they should be able to have a nice relaxing holiday - shouldn't they? Well, no, not really. The Tachyon Recreation Generator, used by the Argolins for the entertainment of their paying guests starts to play up with fatal consequences - but who is behind the scenes, and what does this have to do with the Argolins not getting the income they require to keep their Leisure Planet going? The Doctor and Romana are caught up in events that they really didn't want to have anything to do with, and must seek to redeem not only their holiday, but their lives.
My impressions? A good Fourth Doctor story, but one that just got all a bit muddled somewhere in the telling.