A secondary plot involves Mary Campbell working through her grief over the loss of her cousin, Maggie, aided by Latika.
The episode starkly contrasts how different veterans handle their past. Carlos uses therapy and openness to cope, while John remains an "armored" person, choosing to bury his pain deep inside.
Meg Donnelly (Mary), Drake Rodger (John), JoJo Fleites (Carlos), Nida Khurshid (Latika), and Bianca Kajlich (Millie). "The Winchesters" Masters of War (TV Episode 2022) - IMDb
Viewers learn more about Carlos Cervantez’s time in the military, adding significant emotional weight to his usually free-spirited character.