If you want a cheap flight from Doncaster to Tokyo, you've got one airlines to choose from.
Make sure you use the search options above to search for flights to other airports in Tokyo, not just New Tokyo International Airport. The more options you look at, the better your chance of finding a cheap deal. Just so you know, the flight typically takes 26 hrs 15 mins.
You can expect accommodation prices to be higher at this time of year too. Last-minute deals do crop up, but it's best to book everything in advance to avoid disappointment.