Along the way Clark had to overcome strong influence from his superiors and problems in his private life, most notably the break-up of his marriage following an affair with WPC Jenny Dean (Lesley Vickerage).

Throughout the series Clark was assisted by colleagues Harry Naylor (Tom Georgeson) and Maureen 'Mo' Connell (Siobhan Redmond).

The show became a surprise hit for the BBC, winning a British Academy Television Award (BAFTA) for Best Drama Series in 1994.

At the start of the third series (after a dramatic shoot-out at the end of the second) Clark, Naylor and Connell leave the police force and work in the murky world of private security, far-right political groups and espionage.

Between The Lines was one of the first British TV dramas to include a bisexual character (whose sexual orientation is incidental rather than central to the plot).

Maureen (Mo) Connell (Siobhan Redmond) has two significant romantic partners during the series, a serious boyfriend in season 2, and later on a long-term girlfriend.

While some other police officers are briefly shown making disapproving comments (e.g. when she brings her girlfriend as plus-one to a police social), her bisexuality is shown as completely accepted by close colleagues, if a subject of occasional friendly banter (e.g. Mo mentions having a date that night, Tony asks "girl or boy?"

[7] Guest stars in the series included many well-known British actors who have gone on to star in other major television dramas and/or movies, including Daniel Craig, James Nesbitt, Jerome Flynn, Bernard Hill, David Morrissey, Jaye Griffiths, Paul Brooke, Francesca Annis, Sylvestra Le Touzel, John Hannah, Michael Kitchen, David Hayman, Hermione Norris, Edward Tudor-Pole, Ray Winstone, Larry Lamb, Hugh Bonneville, Marc Warren, Ben Chaplin and Jonny Lee Miller.