Baskerville Military Base was a scientific military research base on Dartmoor, which the government/military used to conduct genetic experiments in secret. Sherlock Holmes used Mycroft Holmes' government security card to get him and Dr John Watson entry into the base, in order to investigate if the lab had produced the giant hound that Henry Knight reported seeing, as a result of some weird genetic experiment. When it was realised that Sherlock was not Mycroft, they were stopped and the base went into lockdown, but they were saved at the last minute when Dr Bob Frankland pretended that he knew Mycroft (a.k.a. Sherlock), and that it must just be a computer error.