Description by couchtuner for Buffy The Vampire Slayer Season 4 Episode 21 : Adam reveals that Riley has a behavior modification chip located just over his heart and wired into his central nervous system. Buffy realizes what Spike is doing and tries to pull the gang back together in time for a final showdown with Adam inside the Initiative itself.
Watch It Here :Buffy The Vampire Slayer Season 4 Episode 21 Primeval (2)