Waking the Dead (2001)

The darker, more forensic British original. Trevor Eve's Peter Boyd runs a London cold case unit, and he is short-tempered, difficult and very watchable, which gives the series a bite the gentler shows lack. Each story runs as two hour-long episodes, enough room for old files, reexamined evidence and the psychology of crimes that sat untouched for years. It ran for nine series up to 2011, so there is a deep back catalogue, though the earliest stories look their age. Pick this one if you like your cold cases grim and your lead detective prickly.