We last saw Sherlock Holmes (Benedict Cumberbatch) as the detective boarded a plane leaving the UK. Suddenly he was called back. Could the evil Moriarty (Andrew Scott) have possibly returned from the dead? “Did you miss me?”.
As the “Six Thatchers” opens, our intrepid Detective sits in a government briefing lead by his brother Mycroft (Mark Gatiss). However, as the elder Holmes quickly finds out, his brother is surfing on what he claims is a natural high. Minutes ago, he was on a mission which likely meant certain death. Now, Sherlock is tweeting up a storm,“#OhWhatABeautifulMorning”. In fact, Holmes is now officially off the hook for the murder of Charles Magnussen (Lars Mikkelsen). The government has decided to doctor the tell-tale footage from the season three finale. They look to Sherlock, what is he going to do?
His response is matter-of-fact. “Wait”. The game is afoot, and he loves the game.
The action quickly moves back to 221B Baker Street. Holmes has found a nice working relationship with Dr. John Watson (Martin Freeman), and a very pregnant Mary (Amanda Abbington). Together, they work case after case after case. It becomes clear, this is how Sherlock waits.
Later, John looks at his phone as he returns home. Strangely, he has 59 missed calls. They quickly realize that Mary is in labor. Before long, the couple are the proud parents of Rosamud Mary. However, Sherlock has not received the news. In fact, he deletes all of John’s texts, especially the ones that begin with “Hi”. He doesn’t learn the baby’s name until the baptism. Even then, he still seems to hold out hope that the child will be named after him.
The threesome continues to successfully work, even as there’s suddenly four of them. As a result, Sherlock finds himself faced with the impossible task of deducing the logic of an infant. He leans over the baby, “If you want to keep the rattle, you do not throw the rattle”. He looks away, right as the toy smacks him in the face.
Later, DI Lestrade (Rupert Graves) has another case for them. While they sit in Baker Street, he tells them about David Wellsbury, a local Cabinet Minister. During the man’s 50th Birthday, he received a call from his son Charlie, who was traveling in Tibet. However, a week later, something “really weird” happened. The police chased a drunk driver into David’s driveway. The car crashed into Charlie’s vehicle, causing an explosion. When the flames cleared, suddenly Charlie’s charred body sat in the passenger seat.
However, the story quickly becomes even more complicated. As Watson scans the medical reports, he reveals the young man had been dead for a week. Sherlock looks intrigued. “Oh, this is a good one. Is it my birthday?”
As they get up to leave, Lestrade turns the topic to fatherhood. Cleaning up after a screaming, demanding infant, he looks to Sherlock and says, “It must be a real change”. John laughs. As the conversation continues, Sherlock looks up. “Are you two having a joke?”.
The team quickly leaves to speak with the Wellsbury family. Entering the sitting room, Sherlock zooms with laser-like focus on a picture of Margaret Thatcher. When asked about it, David calls it a “shrine” to the former Prime Minister. Staring at the set-up, Sherlock notices that something is missing. Mrs. Wellsbury admits that a bust of the Prime Minister recently broke. There had been a break-in, and the family found it smashed on the front porch.
While Sherlock further delves into the details Charlie’s death, he reveals that the boy’s Skype call with his Father was pre-recorded. In fact, Charlie had been hiding in the car, hoping to surprise his father on his birthday. However, Sherlock hypothesizes that during the call, Charlie had some kind of seizure and died. Hence, the body would still have been in the car when it exploded.
Later, Lestrade brings another shattered Thatcher bust to Sherlock. As a result, the detective is intregued. “This is my game face”.
While Sherlock sits with his hacker friend Craig, the man talks about the current call for cold war memorabilia. It turns out, there were only 6 of these exact Thatcher busts made. Meanwhile, Sherlock gets a call from Lestrade. Theres’s been another murder. Someone is wandering around, smashing busts of Thatcher and killing people.
The action jumps to a mansion swimming pool. A shadowy figure appears and moves towards yet another Thatcher bust; however, Sherlock has been waiting. The two men fight. “Goodbye Sherlock Holmes,” the robber says as they crash through a window. They land in the pool, where the fight continues.
“Tell me about your boss Moriarty,” Sherlock says, smashing the bust himself. Inside, he finds a flash drive with “A.G.R.A” scribbled in permanent marker. He flashes back. The flash drive is identical to one Mary had given John. He remembers that it had all of Mary’s dirty secrets on it. With Sherlock briefly distracted, the robber grabs a gun. “Tell her she’s a dead woman walking… I’m the man who’s going to kill your friend”. The man shoots the light sensor, before he sprints from the room.
Later, Sherlock meets Mary in a secret location. He shows her the flash drive. She tells him everything. In fact, she was a member of a covert ops team of four “agents”: Alex, Gabriel, Mary and A.J. They put their backgrounds and aliases are on the flash drive as a form of protection. Each member has a flash drive; as such, each had enough information to bring down the others.
Mary tells Sherlock of their last mission. It was a hostage crisis, and she was the only agent who made it out. She’s stunned as Sherlock produces a picture of the robber. She immediately recognizes him as A.J. “Mary, I’m sorry to tell you this, but he wants you dead”. Mary can’t understand what she’s hearing. They were like family. Mary hands Sherlock a piece of paper. However, it’s filled with sleeping powder.
After a cryptic sea-side flashback, Sherlock wakes up. The flash drive and Mary have both vanished.
Sherlock turns to Mycroft. It turns out, he worked with A.G.R.A.. Mycroft leans forward with an ominous tone. “Agent’s like Mary tend to not reach retirement age. They get retired.”.
Meanwhile, Watson’s heartbroken as he reads a note from Mary. She has left him to go on the run. Mary is a super-secret agent; and as such, she easily blends into her surroundings. She eventually reaches Morocco. Covertly, Mary clad in a headdress, draws a gun and enters a room, but she stops when she hears a familiar voice. Sherlock somehow beat her there. “How did you find me?” Mary asks. “I’m Sherlock Holmes”. Well, and there was a tracer on her flash drive. At the same time, Watson steps out of the darkness, “It was my idea”.
John and Mary share a tender moment alone, but as they finally agree to come back to London, A.J. bursts in. There is an exchange of gunfire. It turns out, while Mary escaped their last mission, the others weren’t dead. In fact, they were captured and were subject to intense torture. Both agents tensely circle each other, their guns drawn. A.J. mentions hearing the voice of an English woman, who he assumed was Mary, betraying them. However, a police officer enters and kills him before he can say any more.
Finally back in London, Watson gets off a bus. He’s been making eye contact with an attractive woman, and she suddenly passed him a note. As he’s about to throw it away, he looks at her phone number. Later, he’s sitting at the table and decides to text her. Out of nowhere, Watson is flirtatiously texting. However, he quickly seems to comes to his senses and calls it off.
Later, Mycroft calls Lady Smallwood (Lindsay Duncan) in for questioning. She was a handler for A.G.R.A. Did she betray them? However, she staunchly maintains her innocence.
Meanwhile, Sherlock walks through the London streets, the actions and conversations of the episode flying through his head. Suddenly, he takes off running.
John and Mary get a text, they’re needed at the London Aquarium. Come immediately. Mary goes, as John must wait for the sitter.
While Sherlock wanders through the aquarium, he comes face to face with Miss. Norberry, a government secretary he’d spoken with during his own questioning. It turns out, it was she who betrayed A.G.R.A. She admits to using them as her own assassination unit in order to line her pockets. However, when she was discovered, she betrayed them on the hostage mission, ridding herself of all her problems at once. She tells him, “A.G.R.A. was killed, or so I thought. My secret was safe”. As Mary enters and takes an aggressive step towards her, the Secretary draws a gun. As Mycroft and Lestrade enter, there’s no way out. “Maybe I can surprise you,” Miss. Norberry says as she fires at Sherlock. Mary leaps in front of him, taking the bullet for Sherlock just as Watson enters.
Watson’s panicked as he holds his dying wife in his arms. Mary looks up at him, tears building in her eyes, “Look after Rosie”. She shifts her glance to Sherlock, “I’m sorry for shooting you that time”. She returns her eyes to her husband as she gets weaker, “You were my whole world”. Watson holds Mary as she dies. He buries his face in her hair, an anguished wail spilling from his throat.
Watson looks up at Sherlock, “Don’t you dare… You made a vow, you swore it”. He kisses his wife, struggling to keep himself in check as his friends hover over him.
Later, a therapist talks slowly to someone. Surprisingly, it’s Sherlock.
Meanwhile, Mycroft enters his kitchen. He sees a sticky note and quickly picks up a phone, “Put me through to Sherrinford, please…”. Will this season introduce the often discussed, but rarely seen third Holmes brother?
As Sherlock and Miss. Hudson (Una Stubbs) sit inside the flat, he is conflicted. He sorts through his mail, and pulls out a DVD. There’s a scribble on the front: Miss Me? However, as he plays the DVD, it’s a message from Mary, not Moriarty. It’s a posthumous message for Sherlock.
Later, he finds himself on Molly’s (Louise Brealey) doorstep. She steps outside, holding Rosie in her arms. She passes Sherlock a note from John. It turns out, a distraught John has gone off on his own. He’s refusing to see, or speak to anyone, especially Sherlock.
As he drives away, Mary’s words play on a loop in Sherlock’s head. “When I’m gone, I need you to do something for me. Save John Watson. Save him Sherlock”.
The fourth season of Sherlock airs Sunday nights on your local PBS station. Previous seasons are available on DVD.