‘The world can look after itself. I’m busy with something normal for a change.’ I really enjoy the tone of this one, and the way it starts as a light comedy, like Mr Smith prissily arguing with the newly-returned K9. There are also strong elements of farce, including K9 bustling about trying to help Rani and Clyde catch an alien as Sarah Jane attempts to hide her uncanny side-line from Peter. This is all summery and sweet, as the December bride brings her new fella home, while Rani, Clyde and Gita rubberneck and K9 forlornly admits he can offer no useful advice to Luke on what to say or how to behave.

But the shadows lengthen as the episode continues. Clyde notices online that Peter’s address looks empty and the house is for sale – a visit confirms it’s mothballed. Meanwhile, a lightning proposal is made, and Sarah Jane starts acting very strangely, ordering Mr Smith to completely deactivate as her engagement ring glows bright red. And while Luke understandably wants to see his mum’s big day run smoothly, and Rani has been distracted by the chance to be bridesmaid, Clyde steps up, looking like he’s cosplaying the Doctor as he points out how odd this all is.

The wedding itself is unsettling – budget and availability presumably dictated the small turnout, but the absence of the Brigadier, Mike and Tom Yates, Maria and Alan Jackson is pointed out as weird. Plus, the sound of the TARDIS trying to materialise keeps wafting through the background of scenes with increasing urgency. So, it’s not hugely surprising either that the Doctor should turn up to stop the wedding, or that the wedding itself is a trap. But I expect a few viewers were surprised when Peter’s angel turns out to be the Trickster – brazenly wearing white.

Next Time: The Wedding of Sarah Jane Smith – Part Two