'NCIS' recap: Does Anthony DiNozzo Jr. have a long-lost sister that Senior is keeping a secret?

Pictured left to right: Michael Weatherly and Robert Wagner on "NCIS." (CBS/Cliff Lipson)

[Spoiler alert! The following contains spoiler for "NCIS."]

It's she said-she said on the "Reasonable Doubts" episode of "NCIS," when the police are called to the scene of the murder of a Navy  Public Affairs officer where two women – his wife and his mistress -- each claim that the other shot him.

Since Laurence Jennings was a Navy employee, the team heads out to take over the investigation. But before they're out the door, Anthony DiNozzo Sr. (Robert Wagner) drops by the NCIS office and offers to do some volunteer work. Junior puts him off.

At the scene, DiNozzo and Bishop test both women for GSR. Both test positive. The time of death is determined to be between 8:30 and 9, which accurately coincides with the time each woman called 911.

Jennings has two bullet wounds: One in the head; one in the heart. Ducky says the shot to the chest tore through his aorta and severed his spinal cord. Then the shooter moved in for the head shot, which was done at close range. There were fibers in the wound that were sent to Abby.

Jennings' wife Angelina tells Bishop that she found out a few days before that her husband had been cheating on her and she moved out. His mistress, JoAnn Allman, a lawyer whose license was suspended for misconduct, tells DiNozzo that a couple of days prior, Jennings called and said he finally told his wife about her.

Each woman said Jennings called them at 7 a.m. Angelina said he told her he was sorry and he was going to tell JoAnn it was over. JoAnn said Jennings told her that Angelina was making threats. Each claimed she saw the other shoot him.

Cut to: DiNozzo Jr. and Sr. leaving a restaurant after lunch when a homeless woman approaches Senior and calls him dad. Junior jokes about having a sister he never knew about.

That evening, Senior goes by Gibbs' house to help him with the boat. He tells Gibbs that moving to DC has been good for him. He likes being close to Junior. Senior tells Gibbs about the homeless woman and how he could have a daughter her age. There was something in her eyes. He feels guilty for walking away. Gibbs suggests Senior make the woman his project.

Junior is home when Senior shows up with his "daughter." Her name is Susan. But she can't remember her last name. Senior wants Junior to find out who she really is. Junior puts them in an Uber and sends them to a homeless shelter. Senior gets Susan's fingerprints and Abby runs them. Her name is Susan Elizabeth Lowe, a former Army corporal, honorably discharged in 1986.

Meanwhile, McGee discovered that Jennings made two large bank deposits totaling more than $500,000 in two separate banks. But now the money is missing.

Gibbs and McGee go to Jennings' office and talk to Lieutenant Paul, who tells them Jennings won the money in the lottery. Paul says that is how Jennings met JoAnn. He needed a lawyer.

Bishop discovers that after Jennings won the money, Angelina went on a shopping spree and when the money ran out, she kept spending, accumulating $40,000 in credit card debt. Her husband cut up her cards the previous week.

DiNozzo found out that the second bank account has a lot of medical charges against it – all for plastic surgery and JoAnn was the lucky recipient. Jennings cut her off, too.

Both women threatened Jennings. Then there is the added element of a $2 million life insurance policy with Angelina as the beneficiary. Gibbs says in order to tell who is lying give them a polygraph. To the question: Did you kill Jennings, neither woman was lying when she said no.

Senior goes back to the shelter but Susan is gone. She got a physical while she was there and has symptoms of what might be a brain tumor. Senior looks for her, but can't find her, so he shows up at Junior's, who has info for him. Both her parents are dead and she has no siblings. But he has a 5-year-old address.

At the old address, Junior and Senior find the building manager who tells them something happened to Susan, and she started to screw up and, as a result, lost her job. He carried her as long as he could, but then the building owner found out. Susan told him she was going to try to find her father. She didn't know he was already dead.

Abby discovers that the fiber found on Jennings' body was from a heating blanket. Ducky says that would put his calculations as to time of death off by as much as 2 hours. The women have alibis for the new TOD. Are they conspiring to hide the truth?

Gibbs asks McGee to find out if anything had been deleted from Jennings' computer. McGee finds a document that was written at 6:37 a.m. and deleted at 8:51 a.m. It was a suicide note left to both women. The head wound was self inflicted. It was suicide. The wound to the body was made when one of the women shot him postmortem because his life insurance had a suicide clause: No payment if the holder dies of suicide within two years of getting the policy. JoAnn and Angelina were arrested and charged with insurance fraud

The DiNozzos find Susan and she is burning up. Junior calls an ambulance. The doctor tells Senior that Susan has a glioblastoma, which in her case is inoperable. She has less than a month to live. Senior pretends he is her father and tells her that he loves her.