There are only two episodes left before "NCIS" wraps up its 13^th season and Tony DiNozzo bows out from the team. But with a rogue spy targeting every agent, will DiNozzo even survive the season?

That seems to be the question on a lot of fans' minds, especially now that one of their own is in critical condition. The previous episode saw Leroy Gibbs (Mark Harmon) receiving high praise for his work from the First Lady of the United States. His team was also able to protect a young boy and take down a dirty cop. However, "Homefront" ended with Senior FBI Special Agent Tobias Fornell (Joe Spano) being shot twice in the chest by an unknown assailant.

Episode 23 will pick up where that shocking cliffhanger ended, with Gibbs' team working alongside the FBI and MI6 as they all hunt down the missing British spy.

A trailer for the upcoming episode, "Dead Letter," underscores the danger that the "NCIS" agents face. The clip starts with Gibbs rushing to follow the gurney carrying Fornell. He's heard asking the doctor if his friend will be OK. The situation becomes even more difficult for Gibbs when Fornell's daughter arrives and hugs the man she considers an uncle.

As the team investigates the crime scene, Gibbs tells Vance (Rocky Carroll) that he has a trail of dead bodies. The "NCIS" director retorts with a reminder that anyone is a potential target. Abby (Pauley Perrette), Bishop (Emily Wickersham), and Gibbs are seen viewing a monitor that shows someone apparently searching through a house. Meanwhile, another scene shows Gibbs talking to someone in the NCIS interrogation room. The embattled team leader demands to know from the suspect why he's looking for Ziva David (Cote de Pablo). The clip ends with a shot of Tony (Michael Weatherly) slowly standing up from his desk, looking shocked by someone's arrival.

Hardcore "NCIS" fans are no doubt hoping Tony's reaction means Ziva has arrived back at their headquarters. Unfortunately, that's unlikely to happen as the actress herself recently admitted she won't be returning for this all-important finale.

But based on some recently released photo stills, it's a safe bet that the surprised look on Tony's face was due to the arrival of Trent Kort (David Dayan Fisher). The former CIA agent was last seen way back in season 8 when Gibbs and his team saved him, along with two other "NCIS" members. What role Kort will play remains to be seen, but there's no question that he can be useful in their hunt for the missing spy.

Fans will also be introduced to two new faces this episode — Sarah Clarke and Duane Henry. The former will take on the role of FBI Special Agent Tess Monroe, while the latter is Clayton Reeves, an MI6 operative. The two characters might be playing a bigger role at "NCIS" in the near future.

CBS is set to air episode 23 of "NCIS" season 13 on May 10, 8 p.m., on CBS.