TV Guide has a synopsis for episode 3.14, “Chuck vs. the Honeymooners”, which airs at 8/7c on April 26:
An adventure awaits Chuck and Sarah in Europe when they encounter Spanish spies on a train. Although lacking any backup, itâ€™s full steam ahead for the couple when they try to derail the spiesâ€™ agenda. And an odd-couple spy team emerges: Casey and Morgan, who set out to help Chuck and Sarah.
NBC should be releasing their synopsis soon, which might give us a tiny bit more information. Sounds like a fun episode!
Updated 4:40PM: NBC just released their official synopsis which gives us a few more clues:
Chuck AND Sarah GO ON A EUROPEAN ADVENTURE – While in Europe, Sarah (Yvonne Strahovski) and Chuck (Zachary Levi) realize theyâ€™re traveling on a train with Spanish spies. Even though theyâ€™re all alone, they decide to take on these rogue agents. Of course, this impromptu mission doesnâ€™t go smoothly. Meanwhile, Beckman (Bonita Friedericy) orders her newest â€œunlikelyâ€ spy team â€“ John Casey (Adam Baldwin) and Morgan Grimes (Joshua Gomez) â€“ to track down the missing couple. Sarah Lancaster, Ryan McPartlin, Scott Krinsky and Vik Sahay also star.