SIMON O'CONNOR/Stuff Grimace the gorilla is in his last year of performing at the TSB Festival of Lights at Pukekura Park. He's frightened parents, entertained kids and even slipped on a banana peel once, and after 15 years Grimace the Gorilla is retiring from New Plymouth's famous park to focus on his own family. Grimace, whose identity has always been a well-kept secret, has just two appearances left at the TSB Festival of Lights in Pukekura Park, after 15 summers swinging in the trees at the New Plymouth District Council-run event. His second to last appearance is on Saturday night and the other is January 16.