Mythos

Mythos is a three-episode paranormal drama, first broadcast in 2018 for BBC Radio 4 and focusing on the Department of Works (also known as simply The Department), a clandestine governmental branch that investigates and combats supernatural occurrences across the UK.

A description from the BBC website describes it thusly: Mythos is a series that looks at British folklore through a quasi-scientific prism. It's laced with sardonic humour, ridiculous situations and insane leaps of logic - but its foundations lie in the stories that have become part of the British cultural DNA over the last two thousand years.

List of Characters
Mary/Marie Lairre, the ghost of a French nun formerly haunting Borley Rectory. She works for the Department and is rendered corporeal by complex enochian wards.

Parker, an agent of the Department and chaos magick practitioner capable of adopting different personalities (Fire, Earth, etc.)

Johnson, Parker and Lairre's boss at the Department.

1x01: Mythos - Mythos
Incidents of death from heart failure have spiked at seven times the national average in a small village in Essex. Agent Lairre investigates.

1x02: Mythos - Glamis
Lairre and Parker accompany their boss Johnson (Tim McInnerny) to Glamis Castle in Scotland, where a secret door has been discovered. The door leads into a folkloric dimension, where monster hunter Libby Ward (Jana Carpenter) is tracking a dangerous monster and has kidnapped an innocent American tourist to use as bait. Time bends, dimensions fragment and our heroes realise that the monster Ward is hunting may be a lot closer to home than they thought.

1x03: Mythos - Albion
A sinkhole opens up beneath the City Of London and Lairre and Parker, fresh from battling Robin Hood and his Merry Men, are tasked by Miranda Hyde (Tracy Ann Oberman) to rescue Johnson from the depths of the city.

Lairre battles an incorrect cultural consensus of British history while Parker channels Modesty Blaise to become the world's greatest secret agent, and together they find themselves facing Gogmagog the Giant as Britain's past erupts through time to destroy the present.