Michael is currently trying to make amends with his family after recently stealing from the Queen Vic by conning Jean Slater.
EastEnders episodes airing later this month also see Michael trying to take care of his wife Janine's business affairs while she is on maternity leave.
However, when Michael asks Janine to make him a signatory to the business accounts, this immediately sparks her suspicions as she still fears that he wants her fortune.
Shepherd, pondering whether Michael is hatching a new scam, told All About Soap: "I'll leave that for the audience to decide. Michael's always hatching a scheme, though - he's always got his eye on the big picture and he already knows what his next move is.
"I think he would argue that he's doing it because he wants everything to run smoothly, but maybe there's another reason he's not telling anybody about."
Asked whether Michael has seen the error of his ways, the actor replied: "There was a moment in the wedding episode where he saw the wreckage he'd caused. But I don't think it's enough to put him on the straight and narrow."
Shepherd added that he is still unsure of what the long-term future holds for Michael and Janine.
He said: "We haven't reached the climax of the storyline yet - I don't know how it ends. Nobody tells me anything. I really love being Michael, though. He's such good fun to play and the writers do seem to enjoy writing for him."
Charlie Brooks, who plays Janine, will be taking a six-month break from EastEnders later this year.