Strange Things are happening to BMX rider Bruno Hoffmann in Berlin | Devil’s Voice

BMX rider Anthony Perrin is trapped in a parallel universe at the Teufelsberg in Berlin -  a spooky communications interception station from the Cold War. His friend Bruno Hoffmann, called by mysterious voices, is heading there to save him by clearing various levels at Teufelsberg with his riding skills. But who is sending these voices? Anthony? The Devil?