Oh, I really am growing to love that theme tune.

The rest? I'm finding it immensely likable. A ghastly, non-committal description that somehow avoids discussing the show's true merits. But, well, liking Lab Rats is a start. It makes you hope that finding it 'hysterical', rather than 'amusing', will follow.

So, let's get the usual complaints out of the way.

One - the editing was as ugh as ever, with clunky cuts, messy close-ups, mid-shot reframings and the expected mess with the laugh track as the sound lurches to cover a change of take. Is this the least technically proficient show on TV right now?

Two - once again ill-judged performances suck the life from otherwise-decent gags. Brian spinning the disorientated Mycroft around to make him think he'd just travelled to work? Spot-on. But McGivern's heavy-handed "Ah, it's a shorter journey than you think" badly needed underplaying... and wasn't.

Three - Mike McShane. God, I cheered when he arrived, glad to have yet another guest star who would find the tone and...oh, what's this? Hmm, just seems to be settling for 'loud and American'. Compared to Dr Kyrtistyges and Inspector Goodman, this is one-note stuff. Though the lines suggest it was also a nothing part on the page. Shame.

Four - the rivalry of two scientists. This should have been the perfect idea for the show. Over-zealous competitive rivalry is a sitcom staple - Cheers got acres of mileage from their Bar Wars episodes, and a show like this is ideal for visualising all kinds of insanely-escalating nonsense. So... how come it all feels a bit 'meh'? (Well, mostly it's because more time is spent discussing, and complaining about, the rivalry than is spent coming up with any clever back-and-forth.)

Five - the execution still falls down on the basics. Cara's panic inside the bee costume is never explained, yet it's meant to fuel the last few minutes of the show. It seems to be an issue of discomfort, maybe claustrophobia, but vagueness does not help you bring your laughs to a peak. 'Did I miss something?' is not a good thing for an audience to be asking. It inhibits the reaction.

Yet it's odd to say that, by a narrow margin, this is probably the most consistent episode of the series so far. Footing is being found.

For a start - yes! - Alex and Cara spend a large part of the episode together , on their own, being funny. Jo Enright continues with her spot-on delivery, and Addison is improving. As with A Donor he's at his best one-on-one, with someone who's got the tone nailed. That he spends the bulk of his screen time riffing in a room with Enright guarantees some proper, consistent giggles.

Secondly, the flow of scenes, and the whole story, is a little smoother. Fewer gags are just dropped in any-old-where, which one assumes comes from the writers gaining confidence in writing 'scenes' rather than 'gags'. Best of all, with a flow like that you can then justifiably pull off neat, unexpected cackles - a brilliant cut to two men and their giant magnet and Cara's 'urinals' walk-by. The surprises work because you're into the rhythm, like a song briefly jumping time signature, whereas before all we could expect was inconsistency.

There also seems to be a better through-line, of remembering what's where and available to use. McShane's glitter camouflage is the last of a three-part visual 'bit' that acquits itself splendidly - from silhouette of the impact, through reveal of the "Tony Hart sex party" outline, to the glittery victim re-inserting himself as a disguise. Splendid. The "There's been a murder" translation runner does the job, too. (Though it fails to justify the final "Oh F -" once again.)

Things still show their workings a little too clearly here and there - an intercom buzzer sequence would have been twice as funny if the device had been established in advance of the scene were it was mis-used - but for the most part set-up and pay-off are kept suitably separate. (And the buzzer sequence did lead to a Top Cat reference that made me clap like an infant.)

I'm also putting in a big 'huzzah' for the loss of the animated scene-to-scene bumpers. They didn't work - were too infrequent to be anything other than unusual - and their loss no doubt contributed to the overall sense that everything did join together.

Overall, then, a slight step forward. And extra points for Mycroft's "That rascally Vaabit" line.