We reach the end of Series One of Jago and Litefoot with The Similarity Engine and I have to confess that, unlike the first three stories in this box set, I didn’t remember a single thing about this story from my first listen, aside from the fact it sees the return of Dr Tulp. As a series finale should, The Similarity Engine ties up plot threads from across the previous stories, as well as loose ends left by the original Companion Chronicle, The Mahogany Murderers.  There are call backs to The Bellova Devil (the Far-Off Travellers Club has been funding Tulp’s experiments) and The Spirit Trap (the mention of another ‘presence’ and travelling the astral plane to the 49th Century.  The wooden dummies of The Mahogany Murderers have here been refined into practically life-like puppets – one of which is a perfect replica of Jago himself.

Tulp’s ultimate plan is revealed.  In his mental trips to the future he has discovered uranium.  He plans to take control of the world’s resources and subsequently rule the world.  His plan is discovered when policemen under the command of Sergeant Quick are going missing.  It turns out many of them are moonlighting at the docks and are being exposed to uranium.  They are suffering from radiation poisoning.  Jago is captured and replaced by a doppleganger but Litefoot sees through the charade.

The final confrontation with Tulp reveals that, whilst traversing the astral plane, he has encountered an alien intelligence.  Eventually it absorbs him.

This was a satisfying end to the season.  The tying up of plot threads is welcome and allows the Jago and Litefoot universe to seem a little more developed.  This feels a more involved adventure than the fairly straightforward format definers of the previous releases; although of course as a story this wouldn’t be able to stand alone.

After focussing on Ellie in the previous story, this adventure sees more time spent with Sergeant Quick; including a fun scene where he accidentally saves Litefoot’s life.  He isn’t developed as much as Ellie but it is good to see him getting more ‘screen’ time.  Jago and Litefoot continue in the roles that have been set out previously: Litefoot is the investigator, initially skirting the fringes of the mystery and gathing clues; whilst Jago gets into the thick of the action.  This has worked well in this series, but I hope their roles are developed a little in Series 2.  I liked Toby Longworth’s performance as Dr Tulp and Matt Steer gives good support to Christopher Benjamin as one of Quick’s missing coppers, Smitty.  Lisa Bowerman only appears briefly as Ellie.

Intriguingly, another thing I had forgotten about this story was that it ends on a cliffhanger.  Bodies drained of blood are being found by Quick’s men but for some reason, Litefoot decides to keep this from Jago declaring it to be a case for Litefoot and Sanders.

I don’t find I’ve a huge amount more to say about this.  I liked it, but as I’ve said before, this series hasn’t set my world on fire.  I am, however, still eager to listen to more.  Big Finish must be doing something right with this series for it to reach 13 box sets before the sad passing of Trevor Baxter (with another being released posthumously).  I really like the leads, the support from Conrad Asquith and Bowerman is solid and the overall atmosphere is a good listen.  I would just like the storylines to expand this universe a little more.