Sinclair is a man who has two co-workers. He does not give up when he tries to steal "The Widow." He wants to accomplish his goal by getting Gigi back. Gigi is "The Widow". According to him, she is located somewhere in Finn Baxter's house. When the Baxter family is out shopping, he, Jessica and Hughes sneak into the house. Unfortunately for them, the Baxter family returns early. While trying to flee, he hits his leg on an object and breaks it. Later, instead of a cast in his leg he is seen wearing a red cast that he made it himself from a pair of red boots. That cast limits his movement and makes an extremely loud sound. When Finn bumps into him, he mistakes him for the ghost that supposedly haunts his house due to the loud noise from the cast. Finn decides to spy on him. He finds out that he is planning to break into his house again. Finn decides to set some traps out for the bandits. When he steps into one of the traps, he gets scared when he thinks it's a ghost. He seems to dislike kids, especially Finn and his sister, Alexis when he and his crew finds them home alone. He is eventually defeated by Finn.
Welcome Mr. Hughes.
How fascinating. Why don't you just shut up.
You, Mr. President, get into the garage (to Hughes).
"We're not a bunch of two-bit bandits."
- He is portrayed by Malcolm McDowell.
- Sinclair is the first villain to be old.