The team tries to find a substitute for Ronnie before Martin dies due to a lack of molecular stability. Meanwhile, Francine startles Joe with unexpected news, and Barry hesitates to become romantically involved with Patty.moreless
Two scientists fall victim to killer bee attacks, and Barry's friends figure that a metahuman is responsible. Meanwhile, Felicity and Ray come to Central City to recruit Cisco's help in repairing Ray's Atom suit, and Ray offers to help. Meanwhile, Iris suspects that Eddie is keeping something from her and demands answers.moreless
Barry finds the man who killed his mother, but soon discovers that his opponent is faster than he can imagine. He turns to Joe and Harrison for help trapping his opponent, but things don't go as planned. Meanwhile, Caitlin discovers that Ronnie is alive and enlists Cisco's help to find him, and Eddie asks Iris to move in with him.moreless
The Trickster escapes from his trial and brainwashes The Flash.
Barry and Tina befriend an android with super strength who is running from a secret government agency that wants to use her as a deadly weapon for assassinations.
When a "dead" criminal's body disappears, Barry is suspected in the crime. The criminal has invented a machine that makes anyone who hears its strange sound waves fall into a deep sleep.
Barry meets an old classmate and gets involved when a new villain, the Mirror Master, arrives in town. The new villain steals a crystal from Star Labs that puts Tina in trouble. Meanwhile, Tina has troubles of her own when her domineering mother comes to town.moreless
A scientist clones Barry without his permission. The clone is physically perfect but emotionally it is still a child.
Captain Cold, who freezes his victims to death, is contracted to kill The Flash.
The Flash and Nightshade team up once again as they go up against a Nightshade imposter.
Jay's killer, Nicholas Pike, tries to destroy The Flash with a missile. Instead of killing him it sends Barry hurtling ten years into the future, where "Mayor" Pike has turned Central City into his criminal empire in Barry's absence.moreless
When Barry has nightmares about Tina betraying him, she puts them both under her scanner that can read one's dreams. Something goes terribly wrong however and his dreams are transferred into her mind. One of the unexpected side effects is that Tina thinks that she is a gang member.moreless
An old friend of Julio's, a jazz musician accused of killing his wife years ago, is scheduled for execution. Barry and Julio race against the clock to prove his innocence.
Barry finds himself up against an unseen criminal who traps Tina and her boss in the lab. Time is crucial since the criminal released a neurotoxin in the building.
Barry befriends Doctor Desmond Powell, who was once a superhero called "Nightshade." When Nightshade's old enemy The Ghost, returns Powell must return to his hero ways.
An assassin who sends a "calling card" in the form of a medal is on the loose in Central City. Only the pieces of a broken medallion that Barry finds are the only clues to the killer.moreless
An orphan boy has information that incriminates a 1960s cult figure, Beauregarde Lesko, who is trying to make a comeback.
A murderer escapes from prison to find his loot and kill Barry's father, the cop who put him away.
Barry is investigating some vandalism that directs The Flash to a church. When he arrives, a mad scientist is able to manipulate The Flash as a supernatural force to do his bidding.
A corrupt D.A. hires a private investigator to learn The Flash's secret identity and then tries to blackmail him into working for him.
A strange case come to Flash's attention. Homeless people are dying and their bodies are disappearing. Tina rekindles a relationship with a former colleague who is an expert in genetic engineering.
Barry Allen, a police forensic scientist is working one night during a terrible thunder storm all alone. Suddenly, a bolt of lightning crashes through the lab window, electrocuting Barry and dousing him in chemicals. Barry survives the accident, and soon learns that he is now able to move at almost incomprehensible speed.
Meanwhile Nicholas Pike, an ex-cop turned gang leader, is seeking revenge against Barry's brother Jay. With the help of Tina McGee, a scientist who works with the ultra-advanced Star Labs, Barry constructs a suit that will withstand his super speed and also conceal his identity so that Pike's men won't retaliate against his loved ones.
Now Barry must find a way to stop Pike before it is too late.