"All good things come to an end. The show is so popular that we don't want it to go downhill, we want to go out on a high," said Pat. But fans may yet see more of popular characters such as politician Dan Clancy, Willie Power and Goretti.
And the antics of villagers Timmy Higgins and Jimmy Bourke may grace our small screens again, if Pat gets his way.
"The show has become an institution on Christmas Day so hopefully we'll come back every year to do that," Shortt explained.
"We're doing a Christmas special this year for the fifth year in a row, and I'd love to keep doing it," he added.
Pat is now ready to move on to new projects, so audiences can expect to see more of his comedy in the future.
"It's a big move for me and for my career to say goodbye to Killinaskully, but hopefully we'll come back with something fresh that will grab people's attention," he added. The comic writer is keeping tight-lipped about his next venture, however.
"I have ideas for a new show with a new style, characters and storyline, but nothing is set in stone yet," he explained.
The next and last series will go out on RTE 1 at 8.30pm, starting tomorrow week, and Pat believes it is the best yet.
The surprises to come include sex-starved Goretti becoming a spiritual medium and Theo falling on hard times.