It seems too simple at first but if you left school with poor Irish then I think you’ll get a fair few pointers. That said, they do say on the first page that it’s’ not a text book and to use a dictionary / grammar support if you want more, or to find a course through Conradh na Gaeilge.

It doesn’t come with audio but does have a two-page guide at the back for pronounciation. Eg: “á - like ‘a’ in call”. There’s a sequel called Irish is Fun-tastic which has a similar layout but more advanced and includes grammar, exercises etc.