Team Fortress 2 has already been on the market for 18 months, but the multiplayer shooter from Valve Software didn’t reach the peak of its popularity until last weekend — thanks in part to this month’s release of Meet the Spy, the latest in a series of machinima shorts Valve produces to introduce the game’s characters. Up until last week, Valve’s director of business development, Jason Holtman, told me in a conference call, TF2 was hitting maximum concurrency numbers of 32,000 players; over Memorial Day weekend, however, that more than doubled to 68,000. (The single best sales day was also last weekend.)

Like the game itself, Valve’s video series is a clever reworking of traditional first-person shooter conventions, eschewing realistic violence and macho fantasy for cartoonish graphics and ironic wit. (In Meet the Sniper, TF2’s ruthless Aussie marksman gets flustered by his disapproving parents.) Meet the Spy is by far the most ambitious installment, depicting a trio of befuddled squaddies who try to locate an enemy agent in their midst, only to be undone by comic mishap and a surprisingly romantic plot twist.

The series was originally based on monologues that Valve writer Erik Wolpaw drafted for internal use, first as audition scripts, then as a reference guide for the voice actors ultimately hired to record the in-game dialog. According to editor and director Marc Scapparo, the plan was always to evolve these movies over successive installments, from mere character sketches to full-fledged shorts. Working with a Wolpaw script, Scapparo and his team spent a month capturing in-game footage for Spy, then another month enhancing it in post-production. As with Valve’s games, the video was constantly screened to test audiences, and iterated according to their feedback. In the original version, for example, the Red spy was unmasked as the Blue spy, which confused many early viewers, especially those not familiar with the game — sending the team back to the studio for a story overhaul. “Humor’s pretty subjective,” as Wolpaw put it to me. “[But] if someone doesn’t understand what they saw, that’s a pretty objective [problem].”

While Meet the Spy was just a single element in the promotion of Team Fortress 2’s latest update, it’s certainly one of the most buzzed about. TF2 lead developer Robin Walker partly attributes this popularity to the fact that Scapparo and Wolpaw are members of the game’s development team, not external marketers. In the Valve development philosophy, he said, “marketing is a game design problem.” Then there’s the buzz you get from unauthorized distribution: Though it was officially put on Steam, Valve’s online distribution service, on May 19, a leaked copy had already been uploaded dozens of times and seen by countless gamers days earlier.

Denying persistent Internet rumors to the contrary, Walker told me the video was not intentionally leaked by the company. However, he added, “We regard [the leak] as an unbridled success,” pointing to the additional burst of press it provoked. The developers even added a last-minute knowing wink to the final product. If you look carefully at the alarm system in the beginning, the “Intruder Alert” signal sits alongside a new warning message: “Leaked Video.”

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