For Sapphire and Steel Fans: Richards, Justin. Time Runners: Freeze-Framed. Time Runners. London: Simon & Schuster, 2007.
Strong on the time travel, weak on anything resembling ethics and politics this is the story of Jamie Grant who slips through a crack in time and becomes a time-runner. The time-runners turn out to have caused the crack in time through which Jamie fell but that's ok. Jamie joins the time-runners to oppose the sinister Darkling Midnight. I never did figure out quite what DM wanted but I suspect I'm not really supposed to because I might agree with him. Good and Evil here seem to rest on the possession of twinkly versus deepset eyes. Yet it's quite a good book with the issues of time-travel dealt with well. Richards has made things difficult for himself by deciding that a person can visit a time as an outsider only once with complex effects.