Frontline takes place during the events of the first game and chronicles Patterson's journey as he fights his way across Europe into Nazi Germany during World War II.

Developed by EA Los Angeles, it was the first Medal of Honor game by the studio after being purchased by Electronic Arts from DreamWorks SKG and Microsoft in February 2000.

Initially the player character begins on the frontlines during D-Day backed up by other computer AI-controlled soldiers with an emphasis on fast action-orientated gun-based gameplay.

As the story progress however, the player character is sent on a variety of other missions including a number of covert and undercover operations in locations such as military bases, German-occupied towns and manors, submarines and countryside settings.

During missions, players can earn medals at the end of each level by meeting requirements such as completions of objectives, eliminating a number of enemies and maintaining a percentage of health throughout, all represented by a bronze, silver or gold star.

Shortly after Patterson completes his mission in Lorient, the OSS discovers that the Germans are building a secret weapon, but their contact in the Dutch Resistance goes missing.

Patterson is sent to drop with the 82nd Airborne during Operation Market Garden to find him, meeting up with the Resistance and learning the contact is being held in a Nazi-occupied manor.

The OSS learns from the contact that the secret weapon is a highly advanced jet fighter called HO-IX, which has the potential to change the tide of airpower over Europe if it reaches production.

The OSS makes contact with Patterson again, informing him that they have tracked down Sturmgeist, and learned he is the officer in charge of the HO-IX project.