The Monarch of the Glen star plays a mobile phone salesman in the first instalment of the ninth series, which will help launch BBC Scotland’s new channel on Sunday.
But Compston, whose character helps Jack and Victor get to grips with the latest gadgets, is not convinced the much-loved pensioners will definitely be calling it a day after this series ends.
Compston, who has a starring role in the new Mary Queen of Scots film, has predicted Ford Kiernan and Greg Hemphill, who write the series as well as play the main characters, would end up reviving the show in 30 years’ time.
Kiernan and Hemphill have vowed Jack and Victor will be taking their final bow at the third Still Game live show, which will be staged at Glasgow’s Hydro arena in the autumn.
Compston, who shot his scenes during a break from filming Line of Duty in Belfast, admitted he was “gutted” to hear of their decision, but said it was better they were able to write their own ending for the sitcom.
He said: “I know the boys as Ford and Greg, but when they put on the make-up and start becoming the characters it really is a very surreal moment.
“It was an epic day. To see the boys do their thing was immense.
“I know the boys are saying it’s done. But the fact that they’re playing old guys, 20, 30, 40 years older than them means that there’s so much scope for them in the future.
"But that depends on the ending. They could literally bring this show back in 30 years time – just using less make-up!
"It’s better the boys taking the decision to end it rather than it being forced upon them. This way, they can actually write an ending.
"It was great for us to actually have a last episode (of Monarch of the Glen). It was really emotional and every character got a proper send off."