“NCIS” starring Mark Harmon (NCIS Special Agent Leroy Jethro Gibbs), David McCallum (Dr. Donald "Ducky" Mallard),  Pauley Perrette (Abby Sciuto) and Sean Murray (NCIS Special Agent Timothy McGee), will have an upcoming episode titled "One Book, Two Covers." It will show Special Agent Nicholas "Nick" Torres, played by Wilmer Valderrama, consulting old case notes for a new investigation. Below is the latest "NCIS" episode guide.

Spoiler alert: This update contains more "NCIS" spoilers. Read on at your own risk.

According to a CBS press release, in "NCIS" Season 14, episode 21, Torres must rely on old case notes as well as his old contacts list. This is in connection with the murder of another Marine which is linked to a former dirt bike gang he was part of. Torres joined the gang for one-year as part of an undercover mission. 

"NCIS" cast 2017

The episode was directed by Terrence O'Hara and written by David J. North. The other "NCIS" cast members Brian Dietzen (Jimmy Palmer), Emily Wickersham (Probationary Agent Eleanor "Ellie" Bishop), Duane Henry (MI6 Officer Clayton Reeves) and Rocky Carroll (NCIS Director Leon Vance), will also appear in "One Book, Two Covers."

"NCIS" IMDb

Aside from the regular cast, the Internet Movie Database (IMDb) also lists James C. Bristow (Alonzo Marcel) and Henri Esteve (Johnny Diggs) as guest stars in this episode. Plus, watch out for Johnny Ray Gill's (Royce Layton) appearance. 

"NCIS" episodes

The episodes before "One Book, Two Covers" are titled "M.I.A.," "The Wall" and "A Bowl Of Cherries." The episodes aired on March 14, March 28 and April 4, respectively.

"M.I.A."

The eighteenth episode of the current season, "M.I.A." is about the NCIS team re-investigating a murder case that was formerly ruled out to be an accidental death in order to fulfill a dying wish of a sailor. Torres was also reminded about a tragic time in his life.

"The Wall"

In "The Wall," which was the nineteenth episode of season 14, the team must work with an ill-tempered Vietnam War veteran named Henry Rogers, who is played by guest star Bruce Mcgill. The case involves the murder of a Marine during a special Honor Flight Network event. Honor Flight Network is a non-profit organization that arranges for veterans to visit the World War II, Korea and Vietnam War Memorials for free.

"A Bowl Of Cherries"

The twentieth episode, "A Bowl Of Cherries," features McGee being asked for help by a vice admiral. The team also tracks down a hacker who infected McGee's laptop, potentially deleting his professional and personal files. Meanwhile, Alex (Jennifer Esposito) takes some time off to assist her mother, Marie Quinn, played by Mercedes Ruehl.

"One Book, Two Covers" will air on April 18. "NCIS" airs every Tuesday from  8-9 pm, ET/PT on the CBS Television Network.

ALSO READ 'NCIS' Season 14 Spoilers: Gibbs And His Team Reluctantly Work With An Annoying Vietnam War Veteran To Solve Another Murder