Pilgrims boss Ian Holloway hopes he'll get a warm reception.
"I think he should get a very good reception," Holloway told the Plymouth Herald.
"If I was an Argyle fan - and I'm adopted one at the moment - I would think he did very well for the club.
"The fact he chose to leave us is nothing to do with him. It was to do with his agent and what the other teams in this standard are paying.
"I don't think for one minute he wasn't proud to play for us.
"If there is anybody who doesn't think he did very well then they should moan at him, but I thought he was terrific for us.
"I was sad to lose him. I thought he was quality on the ball. He was probably the best left-back I have seen with the ball at his feet.
"He's a cross between a winger and a full-back. I think he's a full-back and I told him that, but part of him doesn't like defending sometimes.
"If he can sort that bit out, now he's playing for Cardiff, then it's their gain," added Holloway.
"I think he was a huge part of where Argyle ended up - in the Championship."
Meanwhile a local journalist has told the Echo that Capaldi will face a crowd only too willig to get on his back.