Maybe Felicity is expecting a dull Christmas, but then she stumbles upon a magical Christmas object. For instance, a snow globe that transports her to a different, more wonderful Christmas world. This would be a very interesting plotline full of surprises and adventures for her.
One possible theme could be the joy of giving. Since it's a Christmas story, Molly might be involved in giving a surprise gift that brings happiness to someone else.
One possible plot is that Santa Claus decides to visit a small, forgotten town on Christmas Eve and brings loads of presents, which is a huge surprise for the local children.
One possible plotline could be that Felicity discovers she's pregnant just as a major new threat emerges in Star City. This creates a dilemma for her as she wants to help the team but also protect her unborn child.
One possible theme could be the spirit of giving. Since it's a Christmas story, Kit might receive a surprise that shows how others are thinking of him or her, emphasizing the act of giving.
The story could involve Venom facing a new villain that only appears during Christmas. This villain could be using Christmas magic or technology in an evil way. Venom would then have to figure out the villain's weakness and stop him. Or it could be that Venom gets accidentally involved in a Christmas miracle. Maybe he saves someone who then goes on to spread a lot of Christmas cheer, and Venom starts to believe in the power of Christmas. There could also be a plotline where Venom has to protect a Christmas symbol, like a giant Christmas tree in the city center, from being destroyed by his enemies.
Another plot could be that the wife has made a custom - made Christmas calendar. Each day leading up to Christmas, there was a small hint or gift, but on Christmas day, she presents herself as the final 'gift' in a very sexy and unexpected way. She might be wearing a red ribbon around her body like a present.
Maybe Samantha is invited to a Christmas party at an old, mysterious mansion where she discovers long - lost family secrets and it turns out to be a really heartwarming surprise related to her family's Christmas traditions.
Maybe Troll Face is a misunderstood character in this story. He actually wants to make Christmas more fun but his methods are so strange that everyone initially thinks he's ruining it. So he starts changing the Christmas carols to really wacky versions that at first annoy people but then they start to enjoy.
One common plotline could be that Felicity gets physically injured during some sort of conflict or accident. Maybe she's caught in the crossfire of a battle or a building collapse.
I don't know the exact 'the christmas surprise story', but generally, it might be about a family getting an unexpected gift on Christmas, or perhaps a character finding out a long - lost relative during the Christmas season.