Episode 1
Emma is now training as a forensic chemist - and on the cusp of seeing her mother's murder case finally solved, while Daniel has returned to Dundee to give evidence against Phil.
Episode 2
A second explosion puts pressure on McKinven and Sarah to find and stop the bomber. As Phil's murder trial continues, both Daniel and Emma are feeling the strain.
Episode 3
The task facing McKinven is more daunting than ever, especially now that his wife Azra is joining the investigation. Meanwhile, Kathy's PhD student sees more than she should...
Episode 4
Two suspects derail the investigation as McKinven and Sarah are consumed by their feelings. Kathy's inability to communicate becomes a serious problem.
Episode 5
Another deadly explosion occurs. Sarah and McKinven's growing attachment has consequences, as Kathy suspects Jean the Dean of having a secret to hide.
Episode 6
Sarah works with McKinven to prevent another explosion before making decisions about their future. Kathy realises change is essential, personally and professionally.