Ruby Wax: Sane New World (Edinburgh Fringe)

Having examined depression in her last solo show Losing It, Ruby Wax, the self-proclaimed "poster girl for mental illness", tells us this follow-up is aimed at "the rest of you", ie the non-depressives. Her aim? To enable us to understand and control the negative 'theme tune' that plays on loop in all our heads.

Wax's credentials to discuss mental health aren’t in doubt, considering her recent Masters from Oxford and extensive personal experience. And she can easily keep an audience entertained between the science with a sprinkling of neat lines – "the bi-polars loved my last show, they laughed, they cried…".

But whilst in parts entertaining there’s a lack of any real meaning at the core of Sane New World (which coincides with her well-written book of the same name), leading it to fall between the stools of comedy and lecture.

It all feels rather scattergun. One minute our host is (rather badly) explaining synapses or neoplasticity, the next she’s demonstrating pilates on an exercise ball. The insights, such as they are, are hardly revelatory – "on the toilet, nobody’s a star" – while a focussing exercise conducted with the audience feels token.

A brief Q&A at the end allows Wax to perform at her talkshow persona best, relaxedly bantering between dollops of well-intended advice, but come the end I didn’t feel I’d learnt anything especially useful about either my own mind or hers.

I feel bad for giving the poor review that Wax openly admits to 'writing in her head' on stage. I admire her intentions, but this show needs some serious development to better deliver its aims.

Ruby Wax: Sane New World runs at Assembly Rooms until 7 August

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