The IIB is asked to investigate the death of a popular horror movie actor, who is shot on the set by a prop gun which was presumed to only shoot blanks.
When the IIB captures a con artist, she offers, in exchange for immunity, her help in capturing a notorious killer with whom she has a mysterious history.
The IIB is asked by British Intelligence to investigate when a diplomat is found dead in a hotel room and is missing his cell phone.
While investigating the murder of a mysterious tattooed woman, Toby suspects corporate espionage and blackmail are behind the killing.
After Toby witnesses the suspicious death of a promising young Mixed Martial Arts fighter, he and the IIB probe the secrets of his family and the the nefarious business dealings of two rival leagues.
When the key witness in a mob murder trial is shot, Toby and Michelle are joined in the investigation by an FBI Special Agent who has his own approach to the case. While the witness recovers in hospital, the IIB discovers that there may be more to the case than a mob hit.moreless
Despite Michelle's objections, Toby agrees to go undercover to infiltrate a group of thieves posing as police officers.
When a dead body is found inside a freezer in a storage locker full of stolen goods, Canadian Intelligence asks the IIB to take on the case as the stolen property may have national security implications.
When Tia's friend, investigative reporter Victoria Chan, falls from her fourth floor apartment balcony, Tia is convinced she was pushed and asks Toby and the IIB to look into the situation.
Thieves rob an armored car with military-style armor piercing bullets, killing a police officer in the process. The case is personal for Michelle as she knew the slain officer from the Police Academy.
In the Season 4 premiere, Toby and Michelle go to Vancouver to investigate after a string of high-tech thefts spreads west.