As Snoopy sleeps atop his doghouse, the player is transported into his dreams about the adventures of his alter ego, the "World Famous WWI Flying Ace." The rest of the Peanuts characters are woven into his dream - and thereby the game's narrative - as they pass by the sleeping beagle. Lucy Van Pelt becomes the commander of the Allied forces, Linus and Sally take humorous turns as intelligence officers, while poor Charlie Brown is characteristically cast as a janitor in an Allied airbase. The story moves quickly after Charlie Brown is captured by the Red Baron's minions along with the plans for a secret weapon that could change the course of the war. Snoopy and his co-pilot Woodstock take to the skies in his trusty Sopwith Camel to recover the plans and rescue Snoopy’s hapless owner.

The game mechanics center around third-person action adventure flight in contexts such as aerial races, dogfighting missions, and world exploration. Collectible items in the world unlock plane and weapon upgrades, as well as new character/plane combinations for use in versus multiplayer aerial combat. Hardcore Peanuts fans will recognize the front lines at Verdun, the woods of Montsec and Verdon Gorge as the settings for Snoopy’s original Flying Ace adventures in the comic strip by Charles M. Schulz. The game features 7 of these locations, which often change considerably from mission to mission.

The flight model for Snoopy's Sopwith Camel and the other planes in the game leans heavily towards the fanciful arcade end of the realism spectrum. Controls and collision are forgiving and approachable for younger players, although advanced stunts such as barrel rolls and Immelmans are accessible through button combos for experienced aficionados of the air combat genre. The game includes boss sequences that offer novel variations on its core mechanics. For example, players will battle a flotilla of submarines as Woodstock, being towed behind Snoopy's plane in a toy balsa-wood glider. Here the mechanics are those of a rail shooter, with Snoopy pulling the player along a path while the player contends with a multi-stage boss fight.

Pre-rendered cut scenes advance the narrative between missions as the player returns to a "hub world" represented by Charlie Brown's neighborhood. Here the player can upgrade his plane and weapons at Pig-Pen's Shop or complete a series of tutorials at Marcie's Flight School. The music and voiceovers in these sequences recall the classic Peanuts holiday specials that have been an annual fixture of American television since 1965.