TV Guide 5USA Tuesday

The investigators examine the death of US marine Tommy Hill, who appears to have been fatally stabbed en route to a homecoming party thrown in his honour by his foster family. McGee and Ziva follow a trail of blood that leads them to a mobile phone, while Abby discovers the victim had been trying to hack into Virginia's state website and Ducky's autopsy reveals that Hill had been injected with a sedative

US Navy lieutenant Paul Booth is shot dead while sitting on a park bench. It turns out that the last people he called were his boss, his wife and Penelope Langston - a rebellious academic who also happens to be McGee's grandmother. She says that the victim was an old student of hers who kept in touch, but later reveals she was recruited to work on a special project during the Vietnam War by the head of a top-secret think tank Booth was a member of. Guest starring Lily Tomlin, with Mark Harmon and Sean Murray

A man who died after being knocked down by a van is revealed to be a professional hitman responsible for at least six contract killings - and his next target was to be a navy lieutenant commander. Abby is delighted at being a match for a teenager who needs a kidney transplant, but she is informed that someone else with very similar DNA has also been identified as suitable. Has she found a relative she never knew about?