Nicky Newman was a superstar on Earth, the fifth most famous person in the galaxy and one of the contestants of the 309th Intergalactic Song Contest. He had become tired of the fame and was delighted that the Seventh Doctor and Melanie Bush didn't know who he was.
The 309th Intergalactic Song Contest was secretly a diplomatic convention between Angvia and Golos. Loozly, a terrorist, used Nicky for his plan. Nicky suffered from severe stage fright, allowing Loozly to secretly give him an Angvian personal destructor, which detonated under severe stress. In order to protect the audience, Nicky was stopped from performing, while the Doctor performed in his place and eventually won. (AUDIO: Bang-Bang-A-Boom!)