The footage features in TV series Dolphins: Spy in the Pod The series uses several cameras disguised as sea creatures to film dolphins The mammals were filmed in a trance-like state after eating puffer fish By Alex Ward PUBLISHED: 07:20 EST, 29 December 2013 | UPDATED: 10:21 EST, 29 December 2013 Dolphins have been filmed for the first time chewing on toxic puffer fish, which when digested in small doses can have a 'narcotic-like effect'.