A group of teenagers has ushered Hollywood into uncharted box-office territory. Superbad, a story of three geeky friends' quest for alcohol for a high school party, retained last weekend's attendance title, taking in $18 million in ticket sales. Its 10-day total stands at $68.6 million.

In so doing, Superbad helped Hollywood achieve its first $4 billion summer movie season. While business slowed as parents and kids prepared for school, Hollywood continued its hot streak.

The top 12 movies took in $90.2 million last weekend, up seven percent from the same weekend in 2006. Box office tracker Media By Numbers says Hollywood's $4 billion seasonal tally tops the previous record of $3.95 billion, set in 2004.

Company president Paul Dergarabedian says movies will have grossed $4.15 billion by the time the summer season ends on Labor Day, September 3. That's up eight percent from last summer.

"Whether it be sequels, originals, comedies, action movies or whatever, this particular mix of films brought audiences in a record-breaking way," he said.

However, there is a catch: fewer moviegoers paid more. Factoring in higher ticket prices, Media By Numbers estimated this summer will see 606 million movie tickets sold - only the sixth-highest total in modern Hollywood history. The best summer attendance came in 2002, when 653.4 million tickets were sold.