'The Winchesters' Sneak Peek: John Flashes Back to a Painful Memory (Exclusive)

ET exclusively debuts a first look from Tuesday's episode.

John, Mary and their friends are back on the hunt in the latest episode of The Winchesters.

In Tuesday's hour, titled "Masters of War," the Monster Club find themselves at the center of a case when the details of a veteran's death don't add up. As John (Drake Rodger), Mary (Meg Donnelly), Carlos (Jojo Fleites) and Latika (Nida Khurshid) start to investigate the suspicious circumstances surrounding the soldier's death, they find themselves with more than they bargained for. Of course, it's the Supernatural universe!

ET exclusively premieres a sneak peek from the episode as the Monster Club breaks into a hospital morgue so they can see the strange lacerations and bruising on the veteran's body for themselves. After John, Mary and Latika -- dressed in white doctors' coats and scrubs, thanks mainly to Carlos -- fib their way through when a doctor stops them in their tracks just feet away from the morgue, Carlos unzips himself out of the body bag he's been hiding in this whole time.

They locate the body and begin noticing rather deep cuts that don't jibe with the official cause of death being ruled a suicide. But Mary and Latika aren't buying it, noting that there are too many red flags that say otherwise. John chimes in suggesting that whoever drew the fatal blows was "strong" due to the depth of the lacerations.

But something else catches his eye, a cross necklace that looks all too familiar. Immediately, he flashes back to his time as a soldier in the Vietnam War, suddenly remembering his friend who wore the same necklace, and who had a similar fate -- perishing amid gunfire after stepping on a landmine. The nightmarish memory rocks John to his core.

Though he's taken out of the painful memory seconds later as the foursome hurriedly try to skirt out of trouble, something tells us this is just the beginning.

The Winchesters airs Tuesdays at 8 p.m. ET/PT on The CW.