"Thank you. Kindly tell your employer that Mister Jago wishes to see him urgently."

Despite an inauspicious start, the meeting of Henry Gordon Jago (Christopher Benjamin) and Professor George Litefoot (Trevor Baxter) forty years ago this month in Doctor Who - The Talons of Weng-Chiang marked a friendship that has gone from strength to strength at Big Finish.

It all began with Doctor Who - The Companion Chronicles: The Mahogany Murderers by Andy Lane, which as March's chosen Listeners title is available for £2.99 on Download until the end of the month:

Professor George Litefoot: the eminent pathologist who advises the police in some of their grisliest cases. Henry Gordon Jago: the master of ceremonies at the Alhambra Theatre. These are two very different men from contrasting strata in society who became firm friends and collaborators after their adventure with the Doctor and Leela battling the evil Weng-Chiang.

Some years later, Jago and Litefoot have defeated dangerous denizens of the daemonic darkness together. They have stood side by side against threats to the British Empire. But when a body is found on the banks of the River Thames and Litefoot's post mortum reveals that it is actually a highly detailed wooden mannequin, their most dangerous adventure begins.

Dr Tulp has masterminded a deadly scheme, Jack Yeovil and his murderous gang plan to live forever, and only Jago and Litefoot can stop them...

Doctor Who - The Companion Chronicles: The Mahogany Murderers is available all month for £2.99 on Download. Use the Big Finish app for Android or Apple devices to download and be listening wherever you are.

Jago & Litefoot's adventures continue soon in Jago & Litefoot - Series 13, which can still be pre-ordered for £25 on Download and £30 on CD, the prices going up by £5 at the title's general release at the end of May.

The Infernal Investigators' infamous adventures can all be found here - Jago & Litefoot at Big Finish. And raise a glass of pale ale to them on the occasion of their 40th anniversary!