FORTUNE -- HBO fans take note: Amazon's Prime Instant Video is about to get better.
On Wednesday, Amazon (amzn) announced a content licensing agreement with HBO that makes select HBO programming available to watch on Prime Instant Video starting May 21. The deal is the first streaming arrangement with a subscription service agreed to by the cable network.
The agreement includes older HBO shows, such as The Sopranos, Six Feet Under, and The Wire; earlier seasons of Boardwalk Empire and True Blood; and miniseries, such as Band of Brothers. Older seasons of shows such as Girls and The Newsroom will also join the lineup three years after airing on HBO.
Amazon also announced that HBO GO, the subscriber-only online and mobile streaming service, is coming to its recently launched Fire TV set-top box by the end of the year. The service is already available on competing devices, such as Apple TV and Roku.
Although the HBO deal leaves out hit shows such as Game of Thrones and Sex and the City, it's a big win for Amazon's rapidly growing video streaming service, giving it a significant advantage over its competitors.
The deal expands Fire TV's catalog of 40,000-plus movies and TV episodes with HBO content that won't be available to Netflix (amzn) and other competitors in the near future. The deal also gives the Fire TV device a content advantage over Apple TV (aapl), which lacks access to Prime Instant Video.