He says it was just sleeping pills, followed by Adderall. It's unclear if there's more to it. Damien also seems to have it out for Ben, though his intentions are unclear.
Lily attempted to pay Ben to skip town. He didn't go for it. Serena wants to explore a future with Ben, or at least reconnect with the professor she once looked up to.
Chuck has been sleeping with Raina Thorpe but is put off by the hiring of The Captain by Russell Thorpe. Chuck tries to get The Captain fired, ticking off Raina.
Dan and Blair both land coveted internships at W, then sabotage one another at the magazine's big party and get fired. Dan later gets Blair's job back for her.
(Source: TV Fanatic)