NCIS: Los Angeles will treat fans to a three-part story before season 6 comes to a close.

Who Will Come Between Nell & Eric On 'NCIS: LA'? Ops Will Get Some Help In 'Blaze Of Glory'

The CBS drama will begin shooting episode 21 (filming as 619) on Monday and executive producer Peter Kousakis recently announced that "Beacon" will kick off a three-episode arc.

"#HappySunday #NCISLA begins production on E619 [Diana Valentine] is at the helm. [Jordana Lewis Jaffe] is Scribe. 1st of 3pt. #staytuned #jpkteaser," Kousakis tweeted on Sunday.

Will Deeks 'Fighting Shadows' Trouble Come From Densi? 'NCIS: LA' Team Uncovers The Truth

Jaffe and Valentine are both NCIS: LA vets, each with several episodes under their belts. Most recently, Jaffe penned "Savoir Faire" and "Exposure" while Valentine directed "Forest for the Trees" and "The 3 rd Choir."

While fans wait to find out what multi-part case Callen, Deeks, Sam, and Kensi will take on in "Beacon," NCIS: LA will air "Fighting Shadows," "Blaze of Glory," and "Rage."

The secret of Deeks and Kensi's relationship will come tumbling out in "Fighting Shadows," causing Hetty to switch up the partner situation. "Blaze of Glory" will cause some consternation up in Ops as a new intelligence analyst comes between Nell and Eric before Callen's past comes to the fore once more in "Rage."

Find out more when NCIS: LA airs Mondays at 10 p.m. ET on CBS. Click the video below to see a preview for the series' latest episode, "Savoir Faire."