The USS Nathan James will face an unforeseen foe when they encounter a medical ship that is waiting for Dr. Scott's cure in the new episode of TNT's hit series "The Last Ship."

In the fourth episode, entitled "Solace," things begin to look good for the crew of the U.S. missile destroyer as they spot a new ship at sea that is waiting to produce the much-awaited cure that Dr. Rachel Scott (Rhona Mitra) has discovered.

According to TV Guide, CDR Chandler (Eric Dane) sees this is as an opportunity to add another vessel to the fleet, as a new ship, especially a medical one, has become a necessity. When he and his team boarded the craft, however, tensions rise when they find themselves facing an unforeseen foe. 

The last episode of the series saw the crew of USS Nathan James arriving back in Norfolk after a quick detour to Washington D.C. The destroyer returned home on a mission to distribute the cure and search for their friends and loved ones.

The hunt for survivors led to Mike Slattery's (Adam Baldwin) hometown, Deer Park. He then discovered his wife missing, with no clue on where she may have gone. On a happy note, Lt. Kara Foster (Marissa Neitling) reunited with her mother.

Viewers also got a glimpse of Dr. Niels Sorensen, who was last seen fleeing his Russian captors when their ship exploded. The mad scientist landed on a beach in Florida, leaving a trail of bodies as he wandered into St. Luce's.

The unanticipated enemy theme is not an uncommon scenario throughout the series, Latin Post says. Chandler actually welcome this prospect, as he has gotten used to facing hurdles, and it will just be a matter of time until he figures out the details on how to get his crew to safety.

As for what the new enemy wants, viewers have to watch "The Last Ship's" fourth episode to know. "Solace" will air Sunday, July 5 on TNT.