Killer's Cure

DI Shona McKenzie is hurtled into her most complex case yet, when she is alerted to the unexpected deaths of several women, all of whom were hospital inpatients. All were recovering. 

None should have died. 
None on the same ward.
None in the same hospital. 

Then the case takes an even more sinister turn. Where does Shona even start to solve her latest case and how can she join the pieces together to bring a killer to justice.