Some PC players of Call of Duty: Black Ops II report that disc 2 of their recently-purchased game is the wrong sequel entirely.
Players on the Call of Duty forums, the Steam forums, and Reddit are reporting that when they insert disc 2 as prompted, they receive a Mass Effect 2 read error. The video above (some language NSFW) demonstrates the issue.
The discs in question are correctly printed with the Black Ops II front, but appear to have received the wrong image where it matters: in the software. Clearly, something went awry in the manufacturing.
For most players, this won't be a show-stopping problem. Black Ops II authenticates through Steam, and so once players have associated their game's serial number with their Steam account, they can simply download any missing files.
Call of Duty publisher Activision and Mass Effect publisher EA are, of course, notoriously rivals with some bad blood between them. This manufacturing error is no doubt the only time players will ever find a Call of Duty game and a Mass Effect one in the same case.