(S02E04) Four down, four to go -- and Life on Mars just gets better every week.

I recently read a story in The Guardian that suggested when David E. Kelley re-writes this series for a US audience, Rachelle Lefevre will play a lone female detective who forges a mystic bond with the mysterious time-travelling detective (i.e. Sam Tyler) and teams up with him to track down a serial killer.

Forget all that rubbish.

Just watch this series; it's the best thing on television since Doctor Who returned.

As before, this week's episode followed the pattern in previous weeks where an element of 1970s society was put under the microscope during the course of a criminal investigation.

This time, it was the turn of swingers' parties and Avon ladies -- not that the two are connected in any way, mind you.

One of the key components to the story of an unhinged serial killer was the notion of 1970s police surveillance being free from the shackles of civil liberties and privacy laws. Where, in the present day, wire-tapping, illegal entry and hidden recordings are subject to court orders, in the 1970s, they were all the rage.

Sam, Gene and the team set themselves up with rudimentary bugging equipment to infiltrate a wife-swapping party, with the intention of collaring a wealthy car salesman for the copycat murder of a cosmetics sales girl. However, the identity of the real killer couldn't have been further from their initial suspicions.

As before, we caught some glimpses of Sam's past (or possibly his future) when he encountered his aunt -- who naturally failed to recognize him -- and he started to feel more alone than ever before in his time-travel trap.

It's all too easy to overrate a show because it helps pass an hour on a dull winter Wednesday evening, but as a fan of shows like Battlestar Galactica, Heroes, Lost and Dresden Files -- I would happily take or leave any one of them if I knew I was going to get the opportunity to watch another series of this utterly brilliant sci-fi cop drama.

But, like all good things, it's going to have to come to an end soon -- and we've passed the point of no return now.

Even if we're still none the wiser as to what on earth Sam is doing in 1973.

Music in this week's show included: "Lay Down" by The Strawbs, "I'm Ready" by Frankie Miller, "Court In The Act "by Lindisfarne, "Samba Pa" Ti by Santana, "Coz I Love You" by Slade, "Aladin Sane" by David Bowie, "Rock On" by T Rex, "When The City" Sleeps by Barclay James Harvest and "Alone Again, Naturally" by Gilbert O'Sullivan.