When Russell T Davies brought Doctor Who back in 2005, his first concern was that it should be fun. This is very smart thinking. The possibilities of the series are, after all, endless. If you have the entire universe of time and space at your disposal, and where you are isn’t fun, then by all means find something more fun to do. We can do without a lot of tedious hand-wringing and hair-pulling. We need to get the mass audience back.

The casting of Christopher Eccleston slightly pulled the stories in another direction, and the two strands of tortured lonely god and devil-may-care galactic adventurer were not always perfectly braided together. Much more successful was David Tennant, who pulled off the joie-de-vivre with much more ease and comfort than his predecessor and so made the flashes of angst and pain more significant for being fewer and further between. And so a good series of Doctor Who can and should include heart-breaking episodes like Doomsday and Human Nature as well as those which are just a (horrible word) romp such as Partners in Crime or Tooth and Claw, but the Doctor is usually permitted one scene of headshaking moralising so it doesn’t all seem too glib.

This is what was so profoundly odd about Dinosaurs on a Spaceship. First of all, it’s a complete muddle. Silurians, Rory’s dad, Queen Nefertiti, big game hunters, a sinister trader, comedy robots, dinosaurs – and, of course, a spaceship – assembled virtually at random with no sense of purpose, focus or theme. And it contains a number of things which we haven’t seen before. The Doctor’s new habit of dropping off Mr and Mrs Pond at the end of each adventure and then scooping them up again at the beginning of the next is bothersome. There’s no particular reason for him not to do this, I suppose, but he’s never done it before and I don’t quite understand why he’s doing it now.

This is extended in tonight’s episode in which he also takes Queen Nefertiti from the end of a previous (unseen) adventure and Rupert Graves’ standard-issue great white hunter, not to mention Rory’s dad. “I’ve never had a gang before,” comments the Doctor, hanging a lantern on it. No, and there’s no particular reason to have one now. Except of course, because it might seem fun.

And for once, even the art department lets the side down, with the spaceship interior also a jumble of location work, exteriors (for no good reason) and then a very, very standard-issue spaceship set (possibly reused from an earlier story?). That’s this episode all over – nothing is consistent and yet all the individual pieces seem very familiar. The dinosaurs are faithfully duplicated from the Jurassic Park playbook, even including a big game hunter triangulated by two raptors (if Rupert Graves had said “clever girl” I might have given up altogether). Indira of the Indian Space Association is no different from the countless other stubborn military types we’ve seen before. David Bradley’s Solomon is a carbon copy of venal traders from other stories and Rory’s dad, while brightly played by Mark Williams, is exactly as we might have guessed he’d be.

This all might have played better if the stakes had seemed higher, but the drawback of the characters – especially the Doctor – treating the adventures which follow as a romp is that it becomes harder and harder for the viewer to take it at all seriously. If it’s all just larks, then what’s the point? And, then – right on cue – comes the Doctor’s moralising speech to Solomon.

By the end of the episode, everyone has been issued with their raison d’être – Nefertiti is a prize to be won, Riddell is necessary to fight off raptors, Indira’s missiles will destroy Solomon’s ship instead of the Silurian ark and, most limply of all, the flight controls require two pilots of the same gene… thing.. and that’s why Rory’s dad is there. So that’s why the Doctor suddenly felt the need to assemble a gang. This is dreadfully clunky writing with the basic pieces assembled, but no attempt made whatsoever to smooth over the joins or create any sense of organic growth. And, most unforgivably of all, even having hired two famous comedians to provide the voices, the two comedy robots never say anything even remotely funny.

Reading all this back, it sounds rather as if I didn’t like it, but as bumpy and as clumsy and as over-familiar as it was, much of it was very charming. Matt Smith was as winning as ever – I particularly liked his line-reading of the word “run”, faced with the dinosaurs for the first time. Karen Gillan, although rendered rather redundant by the plethora of other characters, gave good banter and the lovely shot of Mark Williams sipping his tea while looking out over the planet Earth was worth any number of unfunny comedy robots.

This is the trouble with “fun” episodes of Doctor Who. If you scoop up a pick-and-mix of characters and ideas that have worked before, fling them all at the page and keep everybody quipping back-and-forth then you might make a “fun” 45 minutes of television, but at the end of it – what’s the point? If it’s bracingly original, remarkably structured or features a truly astonishing turn from a major guest-star then it may not need to be high drama. But familiar components don’t get any less familiar when you mix-and-match them and clumsy plotting is still clumsy plotting even if you’re lucky enough to have Matt Smith reciting your exposition.

And this still sounds as if I didn’t like it, but it was perfectly entertaining while it was on, it’s just that – with the whole universe to explore, I’m frustrated at being given hand-me-downs. But, you know what, if this is as bad as this series gets, then this could be regarded as a classic year. What worries me is that this is the norm, and that when Chris Chibnall inevitably takes over as show-runner (please, no) we’ll get a lot more like this.

3 out of 5 stars