Our Father - S3-E1
Continuity mistake: When Dexter gets out of the car and talks to his sister, the strap on the camera keeps flipping back and forth. (00:52:45)
Our Father - S3-E1
Continuity mistake: When Dexter and Vince are next to the dead girl, in the side shot, the tied string from her top is visible on her back and her hair is to the side. But in the overhead shot of her, her hair is covering the tied string and spread more over her back.
The Lion Sleeps Tonight - S3-E3
Continuity mistake: A man in a blue t-shirt and holding two beer cups is seen walking in front across Dexter and Miguel. In the next shot the same man is seen walking behind them. (00:15:40)
Continuity mistake: Deborah walks out with the yellow shirted man in front of her. Next shot after Quin leaves, the same man re-exits the room. (00:14:00)
Continuity mistake: When Dexter leaves on his boat there are fishing poles behind his seat, but when he turns back around and you see him going away on the boat they have gone.
Easy as Pie - S3-E7
Continuity mistake: When Dexter and Rita are having dinner at Miguel's house, his wife drops a glass. She sets 2 other glasses on the island in the kitchen. After a cut to another shot the 2 glasses are now on the counter by the sink, before she bends down and picks up the glass she dropped. (00:39:50)
Continuity mistake: In the scene where Dexter is playing a video game on Miguel's office computer, Miguel is shown to close the game down. But in the next shot the game is visible on the screen before disappearing again in the shot afterwards. Additionally, the video game shown is Halo 3, which is only available on Xbox 360. When Miguel 'closes' the game, he is actually alt-tabbing from a "TWVidpla" window to "Plaindesktop.bmp," and a laptop battery indicator is visible. (00:12:55)
Answer: No, Harry is not the real father. While he did have an affair with Dexter's biological mother (Laura Moser), this was when she was his C.I. Dexter was already born at that point.