(Review is of both parts).
A young Oxford professor, a mathematical genius, is killed by a parcel bomb. There are plenty of suspects: his wife as he had affairs with several of his students, a former researcher as he cut her out of the credit for a major breakthrough, the parents of a woman he apparently drove to suicide. It's up to Lewis and Hathaway to figure out who did it.
A decent send-off to the show. A fairly intriguing, though a smidge far-fetched, murder mystery. Once again the personal side feels a bit flat: the Hathaway's father saga drags on, Lewis and Dr Hobson are off to New Zealand.
I am glad it ended though: it was becoming rather formulaic and had reached its natural end with the finale of Season 6. The 2-part episodes the producers created to extend the series weren't bad but weren't brilliant either and did feel like they were just trying to milk the last dollar out of the show.