"Behind Enemy Lines" is a military system covering U.S. soldiers on the Western Front in World War II. Skill and combat rules are fairly simple, as they are descended from the original "Traveller" systems. In the first edition, the "Character Generation and Basic Rules" book (96 pages) covers character creation, combat, maps, interrogation, and special units. The "Event Tables" book (48 pages) is full of randomized tables for covering almost any kind of situation: encounters in woods, towns, and fortifications; on railroads; for parachuting and mountain climbing; etc. The "Missions" book (56 pages) has three scenarios, four miniscenarios, and numerous "pregenerated" NPCs. In the second edition, all this material is reorganized into a "Soldier's Handbook" (32 pages), a "Commander's Manual" (32 pages), an "Operations Book" (16 pages), and an Infantry Reference Data sheet.