Venus In Copper: Lindsey Davis

Things are going well for Marcus Didius Falco, ancient Rome's investigator: he hates sharing a cell with a rodent, although being bailed by his old mother is almost as embarrassing; his highborn girlfriend can't decide if she wants him and Titus Caesar's reward for past services is disappointing to say the least.
Hoping for a better life, or at least a better apartment, he takes on new clients.
On the elegant slopes of the Pincian Hill, three freedmen with two flashy wives are under by a clever redhead. Severina Zotica has a foul-mouthed parrot, an odd connection with a snake dancer - and a very suspicious past.
As he pursues this flame-haired fortune-hunter, Falco finds himself beset by violent rent-racketeers, poisoners, and women without consciences who have dangerous designs on him...