There is a certain snobbery within fandom where spinoffs are concerned. Everyone has their own opinions about "canon" – some are prepared to quietly enjoy whatever they believe to be "real" while others will seek to force their opinions on everyone and anyone that will listen. Amongst those that will happily accept the existence of the books and the audio plays there often sits a belief that the books are somehow more mature than the audio plays. There is a depth and intellectual value that can only come from reading a novel – merely listening to a CD is for plebs. Ever since the New Adventures promoted themselves as "broader and deeper" than the television series there has been this idea that the book ranges are more complicated and more respectable.

All of which brings me to Iris Wildthyme. She was created in the book range by a reputable author called Paul Magrs. She is a Time Lady whose Tardis is a double decker bus and who enjoys drinking, smoking, telling rude jokes and generally being a dotty old woman. Coming as she does from the world of print this is somehow thought of as a clever satire, a witty pastiche of Doctor Who clichés, a stimulating reversal of roles which makes us question all manner of things.

Had Excelis Dawns been Iris’s first appearance as a character and had she been created by, say, Gary Russell or Nicholas Briggs, she would’ve been absolutely slaughtered by listeners. Had Big Finish dared to invent such a character they would’ve been reviled and ridiculed by all and sundry (especially sundry). Indeed, they created a similar character for the Unbound play "Exile" and were reviled and ridiculed by all and sundry (especially sundry). So whether Iris is a good creation or a bad creation depends, in part at least, whether her literary origins impress you.

There is nothing especially wrong with Iris Wildthyme. Katy Manning was excellent casting and throws herself into the part like a Roboman into the Thames. She has some good lines – my favourite being her experience of The Death Zone on Gallifrey with seven of her other selves and all "the rubbish monsters". The problem for me was that I didn’t know much about Iris and was left wondering why she had a Tardis bus (as opposed to a Tardis which merely looks like a police box), and more importantly who exactly she was. Based solely on Excelis Dawns you could be forgiven for thinking she is nothing more than a poor quality joke (as in Exile). A bungled spoof of the Doctor which is made worse by her playing opposite Peter Davison’s Doctor. Katy’s "big" portrayal drowns out Davison’s more reserved Doctor and would’ve been much better suited to Colin Baker’s performance.

The play opens with Iris in a nunnery. We’re supposed to be highly amused, "Iris Wildthmye is a nun?!? AHAHAHAHAHA". Because Iris is a wild and debauched old lady who is the very opposite of a nun. You see? Except you wouldn’t, not if you hadn’t read the books she’d appeared in. They don’t even explain why Iris is in a nunnery. It appears the joke about Iris being a nun was the reason why she was a nun. Iris is presented "as is" with no background, no explanation, no context.

The Doctor by contrast has too much explanation. We’re told the story takes place during "Frontios" – while the Doctor is en route back to Frontios having dropped Gravis off on a safe planet. Heaven knows why they gave us this wholly unnecessary detail. So what if the Fifth Doctor never travelled alone on TV? He also never met a dotty old woman who wanted to shag him on TV either. The only possible reason for adding this little nugget of detail is that without it a lot of us wouldn’t have remembered Peter Davison was even there. By adding a contentious detail like that (a point of continuity sure to get the internet buzzing) we are at least reminded that the Doctor was in the story and that it wasn’t simply Iris Wildthyme and a gruff voiced Giles from Buffy the Vampire Slayer searching for a handbag in a land of zombies.

Taken on its own Excelis Dawns is an occasionally amusing and reasonably entertaining hour and a half. As a stand alone story it might be better thought of, as a novel it would probably be considered superb. As the first part of a series it is weak. There is nothing in it that would compel the listener to buy part two. There are no questions which we would reasonably expect to be answered and the land of Excelis is far too uninteresting to want to return to.