Not-Quite Professor River Song never met a riddle she didn’t like and this is a doozie: pages of her diary recovered in an old Earth house. One she’s never been to. So, with Hugo (Mark Elstob) her virtual assistant in tow, River investigates. The second she does, an invisible barrier drops and River finds herself trapped within the house and its grounds. Moving backwards and forwards through time, she becomes part of the lives of the Mortimer family. Love, death, marriages, binge watching – River sees it all as she slowly discovers how and why she’s trapped.

I want, very badly, to see the diagrams Tim Foley used to plot this story because I suspect they’re as beautiful as they’re complex. Moving up and down the family’s history in 26 year increments, River meets everyone from the embittered and estranged grandparents who define so much of what follows them to the gloriously ramshackle gay couple who inherit the house in 2014. Foley makes a massive story out of countless small ones, each life full of joy and tragedy and each life either defined or witnessed by River and Hugo. It’s a near impossible balancing act, combining the gradual solving of the puzzle that is the house with resolving these lives, often in non-linear ways and Foley lands it all.

On top of all that, he also shows us how this experience changes River forever, taking her from the carefully detached figure she’s often appeared to be and turning that into a family’s unofficial patron saint. There’s a moment in the final episode here which has real Gallifreyan fire to it and it’s followed not long after by a heartbreaking and sweet goodbye scene that also ties off yet another plot.

Foley has solved this puzzle in three different directions at once and it’s honestly breathtaking. There’s one reveal in particular, about River’s mysterious adversary, the house Cook (Phyllida Nash) that made me all but applaud. This is audio drama as close up magic. Everything you need is in front of you. You still won’t see the rabbit until it appears. As if that wasn’t enough, there isn’t a beat here that plays out how you’d expect. The core solution to the entire plot is breathtakingly kind and audacious and River to the core. Kind, clear-eyed, pragmatic and so, so flashy.

Foley isn’t the only star player here. Director Ken Bentley and sound designer Howard Carter do great work throughout, especially on a cross-time phone call we hear from both directions. Likewise the effects on Elstob, who’s superb here as usual, give you a pleasingly tactile sense of Hugo’s unique presence. The cast too are uniformly excellent which is no surprise given Kingston, Elstob, Nash, Isla Blair and Wendy Craig in the cast. Nash is especially great – Cook is a presence as warm and comforting as she is increasingly threatening. Ronak Patani and Vineeta Rishi are especially good too, both embodying Foley’s core idea of taking a character you think is familiar and pushing them into new, more complex, better ground.

Verdict: This is audacious storytelling in every way and it works in every way too. You never see what’s happening coming, you’re never left behind, and by the end of the set you’re left vastly impressed by the achievement. One of the most complex and personal time travel stories I’ve heard from Big Finish and one of the best too. 10/10

Alasdair Stuart

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