It may be a cliché but I just can’t help myself – Detectorists is a hidden treasure.

The fact it’s been tucked away on BBC4 has helped to ensure that it’s never achieved mainstream status, but I don’t feel this is necessarily a negative.  For the viewers it helps to create a sense that this is our programme, something we’ve discovered and cherish just that little bit more because it’s not topping the ratings each week.  As for Mackenzie Crook (the writer, actor and director) had Detectorists been a successful BBC1 programme then the pressure to keep that success going would no doubt have been just a little greater.  Although since it won the 2015 BAFTA for Best Situation Comedy, no doubt he may have felt just a little pressure anyway ….

Andy (Crook) and Lance (Toby Jones) spend their leisure time metal detecting.  As members of the Danebury Metal Detecting Club (DMDC), they share their passion with others who – like Andy and Lance – could be said to exist somewhat on the fringes of society.  But whilst the small band of DMDC brothers and sisters may be slightly dysfunctional, one of the strengths of Detectorists is that Crook’s writing is never judgemental or designed to generate a cheap laugh.

Instead, there’s a feeling of warmth and inclusiveness that permeates each episode.  This is a difficult balancing act to achieve – a touch too much pathos and things are liable to turn mawkish and sentimental – but Crook rarely puts a foot wrong on this score.

As the first series opens, we find Andy and Lance fruitlessly searching for treasure (alas, they’re more inclined to discover a bewildering variety of ring-pulls).  Their dream – especially that of Lance – to one day find something of historical importance is a running theme, but it quickly becomes clear, as Crook has confirmed, that the core of Detectorists is the relationship between Andy and Lance (so their hobby could have been anything which appears, at first glance, to be inexplicable to the majority).

It’s when they down tools and mull over the important issues of the day (how many questions they got right on last night’s University Challenge, for example) that the series first begins to spark into life.  But their musings about television quiz shows give way later in the series to deeper matters – as both begin to open up about their respective relationship issues.  And it’s this deeply nuanced byplay which really impresses – a depiction of male friendship which doesn’t rely on the scatological (Men Behaving Badly) is a rare thing indeed.

Andy’s relationship with his girlfriend Becky (Rachael Stirling) hits a few bumps during the various series.  In series one, the arrival of Sophie (Aimee-Ffion Edwards), an attractive young history student, sows discord between Andy and Becky whilst in series two, the pair have an important life decision to make – Becky is keen to move abroad for a while whilst Andy is equally keen to stay at home.

Meanwhile Lance also has his fair share of domestic problems.  His ex-wife Maggie (Lucy Benjamin) is a very needy character, despite the fact that she has a capable – if lazy – new boyfriend.  It’s testament to Crook’s writing that even early on, when the characters had barely been established, we feel for the unfortunate Lance – endlessly manipulated by the hideous new-age Maggie (a wonderfully self-centered performance by Lucy Benjamin).

And although she’s gone by series two (before making a memorable reappearance in series three) that doesn’t mean that Lance’s life became any less complicated.  The arrival of Kate (Alexa Davies), the grown-up daughter he’s meeting for the first time, sends him into something of a tailspin whilst Toni (Rebecca Callard) is everything that Maggie isn’t – a loving, warm-hearted individual who seems just right for him.  But the path of true love is never smooth …..

Each of the three series has a running metal-detecting sub-plot.  In the first, the DMDC clash with a rival club, led by two individuals – Art (Simon Farnaby) and Paul (Paul Lee) -who bear an uncanny resemblance to a singing duo whose name escapes me.  In series two, a young German called Peter (Daniel Donskoy) becomes a love-interest for Sophie whilst also attempting to locate a crashed WW2 plane. In series three, both Andy and Lance are on the hunt for treasure, although for Andy it’s a race against time (he’s desperate to buy his dream cottage – but without making a stunning find this seems unlikely).

Detectorists might be centered around Andy and Lance, but it’s a true ensemble production which allows every cast member their moment to shine.  Gerard Horan and Sophie Thompson, as Terry and Sheila, are both simply divine.  Terry is the president of the DMDC (grander than it sounds, since membership never seems to edge into double figures) whilst Sheila is his ever-helpful wife, always present at meetings in order to provide refreshments (although you’d be well advised never to touch her lemonade).  She’s gloriously disconnected from the real world whilst Terry is highly pedantic but strangely lovable (Horan’s possibly best known for playing a not totally dissimilar character – Charisma – in London’s Burning).

Since Andy and Lance are something of an inseparable partnership, it’s logical that the other members of the DMDC are also paired up.  Although Louise (Laura Checkley) and Varde (Orion Ben) are in a relationship, this is handled in a very matter-of-fact way (they’re a couple, and that’s that).  Clearly with Varde, less is more as we don’t actually hear her speak until the middle of the second series.

A far less likely combination – although with them it’s strictly business – is Russell (Pearce Quigley) and Hugh (Divian Ladwa).  One of my favourite moments across all three series occurs when an incredulous Russell discovers that Hugh’s in his thirties (and therefore isn’t, as he’d previously assumed, a teenager).  It’s also hard to beat the sequences, also in series two, where the pair search for the Mayor’s chain of office, which he lost in a very strange place indeed.

Art and Paul have some of their finest moments during the third series. Paul develops an independent streak whilst both are involved in a hair-raising low-speed chase with Andy and Lance. That they also have a secret identity (as Batmen) comes as something of a surprise.

And whilst she may only feature fleetingly, Diana Rigg as Becky’s mother Veronica adds a dash of star quality to the cast.  It isn’t the first time that the real-life mother and daughter partnership of Rigg and Stirling have worked together, although it’s highly characteristic that the very diffident Crook was initially reluctant to approach her.  Mackenzie Crook has nothing of the bluster and self-importance of, say, Ricky Gervais – although maybe it’s precisely this seeming lack of ego (which appears to bleed into the programme) that is so attractive.

Each of the three series boasts substantial making-of documentaries – Discovering Detectorists (24″34′) on series one, A Day Out With The Detectorists (31″53′) on series two and Welcome to the Clubhouse (27″53′) on series three.  The series three disc also has interviews with Diana Rigg (5″09′), Mackenzie Crook (08″17′) and Sophie Thompson (07″04′).

It seems that Detectorists has now run its course (although Crook made similar comments after the second run).  A pity if so, but it’s wise to quit when you’re ahead I guess.  If there aren’t going to be any more episodes then this boxset is the ideal time to jump aboard if you’ve yet to sample the series.  And if you are a newcomer then I don’t think you’ll be disappointed as Mackenzie Crook has crafted a programme which can easily hold its own against some of the sitcom greats of the past.

Detectorists – Series One to Three (including the 2015 Christmas Special) is released by Acorn on the 18th of December 2017.  RRP £39.99.