The Secretary of the Navy has a special request that Agents Gibbs (Mark Harmon) and his team will not be able to turn down in the upcoming episode of the long-running CBS series "NCIS."

In "Blood Brothers," CarterMatt reports that the team will be asked to help a sailor who is battling with leukemia. The man needs a bone marrow transplant the soonest way possible. With his two siblings dead while doing their duties as Marines, the patient has no other recourse but to find a match outside the family. The secretary is aware of what the family is going through and he wants to help. The sailor will die if he is not given immediate medical attention. Will the Naval Criminal Investigative Service (NCIS) be able to locate a sponsor?

Meanwhile, Agent Bishop (Emily Wickersham) will return to Oklahoma to celebrate Thanksgiving with her mother. After learning of husband Jake's (Jamie Bamber) infidelity, she wants space to think things over and decide whether to end the marriage or not. Last episode, Bishop finally learned the reason why Jake had been acting weird for months. She previously thought it was an affair, until she saw him talking with Taylor Matthews (Lindsey McKeon) of the National Security Agency (NSA) in a restaurant.

Foolishly, Bishop believed that Taylor was investigating Jake for a busted mission back in Dubai. She even asked for Gibbs' advice on how she could help him open up to her. It turned out her first suspicion was correct, after all. Jake was having an affair with Taylor and they even frequent their favorite restaurant. Now, Bishop will travel to her hometown alone to lick her wounds. Will she still accept Jake or is this the end of their marriage?

Also last episode, the NCIS cleared the name of a petty officer (PO) who was being suspected of murdering his ex-girlfriend. The court decided that the evidence against him was inadmissible and he was given his walking papers. The PO wanted to prove to his pregnant wife that he was innocent of the crime so he asked the NCIS to investigate him for murder once again. It turned out the prosecutor was the one who murdered the woman, who was a heroin addict. He was her supplier but things got dicey between them and he killed her.

"NCIS" season 13 airs Tuesdays at 8 p.m. EST on CBS.