Lovers of real life crime documentaries were treated to some deep, dark, compelling stuff in Channel 4′s Interview With A Murderer.

Similar to Netflix’s Making A Murderer and US podcast Serial, the one-off 90 minute show tapped into the genre that’s been continually growing in popularity.

L-R, Prof David Wilson and suspect Bert Spencer (Channel 4)L-R, Prof David Wilson and suspect Bert Spencer (Channel 4)

Respected criminologist Professor David Wilson interviewed Bert Spencer, a former ambulance driver and key suspect in the murder of 13-year-old paper boy Carl Bridgewater in 1978.

Carl was shot at point blank range in the head while delivering newspapers at Yew Tree Farm in Prestwood, Staffordshire – the place where Bert worked and had a license to shoot, although he initially held this information back from police.

david wilson and bert Spencer in bert's house (Screengrab/Channel 4)Viewers praised how ‘normal’ Professor David was around Bert Spencer (Screengrab/Channel 4)

Bert became a key suspect in the murder investigation due to his ownership of a shotgun, his interest in antiques – it is believed that Carl disturbed an antique robbery and was shot as a result – and witnesses statements that appeared to place his car at the scene.

But Bert was never charged for the crime and has long protested his innocence.

As Professor David re-examined the evidence, viewers really couldn’t work out what to make of Bert.

They thought Professor David came across really well and was doing an incredible job of speaking to Bert normally – even when he flipped out at him (which happened a lot).

Viewers were truly gripped and really don’t know what to make of it all – and it’s bound to make some interesting discussion in the office tomorrow.