Spoiler Warning: This page contains plot details of the story in Grand Theft Auto V.
Haines was born in 1975 and joined the FIB in 1993. During his time with the FIB, he worked his way up the ranks so that he was eventually a leader of his own FIB special unit and became the senior officer of many special agents.
Whilst Haines was working for the FIB, in 2008 he was chosen to become the host of a criminal reality TV show called the “Underbelly of Paradise”. Haines and his camera crew would regularly report on gang activity within Los Santos and as the show went on to become a huge success, he thus became a celebrity.
Even though Haines became a huge success with the Bureau, he and his partner Andreas Sanchez were infamously corrupt. It was revealed that Haines was on the payroll of wealthy and powerful people, including Devin Weston.
Haines, who is Dave Norton’s superior, uses him to coerce Michael De Santa, Franklin Clinton and Trevor Philips to do several jobs for him and the FIB in order to increase their funding. One of the first jobs that Haines instructs the trio to do is breaking into the IAA Headquarters in Pillbox Hill and kidnap a man held prisoner there called Ferdinand Kerimov.
After the crew successfully kidnaps Kerimov, Trevor and Haines later torture him to get information about a man named Tahir Javan, who is suspected to be involved with Azerbaijani terrorists. After Javan is killed by Michael with a sniper rifle, Haines orders Trevor to kill him.
Instead of killing Kerimov, Trevor drives him to the Los Santos International Airport and tells him to get on a plane to another country and become a torture advocate.
Michael, Franklin and Trevor later meet up with Haines, Norton and Sanchez at the Murrieta Oil Field. Haines explains his plan to sabotage the IAA. He says that they need to rob a government Securicar which contains valuable bonds which Haines can use to his advantage against the IAA.
He believes that the IAA will use these government bonds to finance gang warfare. The trio grab boiler suits and masks to hide their identity and use a trash truck to block the Securicar on the road. They then use a tow truck and smash into the Securicar to steal the bonds. A huge amount of police enforcements arrive at the scene which the trio fight off and they eventually escape in their getaway vehicle.
Later on, Trevor and Michael have to go into hiding when Trevor assaults Martin Madrazo and kidnaps his wife, Patricia. During this time, Haines wants the FIB to raid an IAA compound where according to Haines, the IAA is developing an experimental neurotoxin. He believes they plan to release in a metropolitan area as part of a staged terrorist plot so that they can get their funding increased by the government.
Before the trio can start the raid, they need to get enough funds so that they can purchase the necessary equipment that the raid requires. Michael, Franklin and Trevor contact Lester and they plan to rob the Blaine County Savings Bank. They successfully acquire more than enough funds for the raid after fighting off the local police department.
The start of the raid begins with the trio meeting Haines and Norton at Cape Catfish. Once Haines and Norton find out that the Michael, Franklin and Trevor didn’t bring someone to help them with the job. Haines and Norton reluctantly assist them with the raid.
Once the crew steal the experimental neurotoxin from the research facility, they have to fight there way through unexpected IAA reinforcements. As they leave the facility, Haines buys them more time to escape in the helicopter by shooting himself in the leg.
Because Haines was present during the raid of the IAA research facility, the Bureau begin to speculate on his corrupt behaviour and operations. This causes Haines to become extremely paranoid about whatt he Bureau have on him.
He orders Michael to break into the FIB headquarters and steal any information that the Bureau may have which could lead to his arrest. He promises Michael that this would be his last job and would be cut loose after he has finished the job.
Michael gets a crew together and with Franklin’s assistance, they successfully raid the FIB headquarters and destroy any evidence that the Bureau has on Haines but also any evidence that Haines had on Michael and his friends, destroying Steve’s leverage over them.
Even though all evidence of Haines’ corrupt behaviour is now destroyed, he still remains paranoid and fears that he will be caught red-handed. He attempts to blame all of his illegal operations on Michael and Norton by calling a meeting with them and Sanchez at the Kortz Center, and once they all arrive he tries to arrest Michael and Norton.
Just when Haines has Michael at gun point, a rival FIB team arrive and Haines reveals that his right-hand man, Agent Sanchez, has betrayed him. Just then, Merryweather enforcements in a helicopter and IAA agents led by the United Liberty Paper Contact arrive, causing a mexican stand-off with all four officials.
This causes a shoot-out, Haines gets shot in the leg by the FIB team and as he falls to the ground shoots Sanchez in the head before escaping. Michael and Norton are left to fend for themselves, they fight there way out of the Kortz Center and escape the Merryweather helicopter.
A while later after the Kortz Center incident, Haines wants to have Michael, Franklin and Trevor killed. Norton persuades him to calm down and convinces him to spare Michael and Franklin but insits that Trevor has to be killed because of his unpredictable psychological behaviour.
Haines and Norton meet Franklin at his aunt’s house in Strawberry and order him to do the killing.