Escape Nettetal: The secret of the white Lady

At the end of the 1950s, the successful chess player Liz Harmonika disappeared without a trace the night before the most important game of her career was to come to an end.
The Russian secret service is probably behind it, who want to prevent her from defeating the previously undefeated grandmaster Vadim Popow.
Your task is now to find out how the game can still be successfully completed - time is short.