'Professor T' Achieves Personal Progress & Unravels “The Perfect Murder”

We've reached the penultimate episode of Professor T Season 4, and everyone's personal lives are in flux. Zelda’s story is taking prominence, and the Dean becomes a less shallow and more fully-fledged character. Though Peter Snares seems like a lovely man, the Dean’s heartache at seeing his one true love slipping away is quite compelling. You feel crushed along with him when he selflessly advises Peter to propose to Zelda. Meanwhile, feeling guilty, Ms. Snares comes clean to Jasper about the surreptitious paternity test she ran on him and the Dean. 

(Ed Note: Good to see Douglas Reith thriving post-Downton Abbey.)

She surrenders the unopened envelope, but Jasper can’t bring himself to look at the results. Dr. Goldberg helps Jasper process his uncertain patrilineage while managing complicated feelings about him. The professor continues making steady strides towards repairing his mental health. The prospect of the Dean being his father gives him a renewed sense of self. With the encouragement of his drum teacher, Lydia, the gloves are starting to come off – literally. Jasper cuts off a few more gloved fingertips, ostensibly to play better, but really a slow dismantling of the walls he’s built around himself.

Dr. Goldberg announces his progress is significant even before seeing the gloves, declaring it their last session. Does she believe that, or is she cutting him loose to avoid an ethical quagmire? With her own therapist, she sounds defensive about inviting him to a restaurant and insists Jasper’s abrasive, rigid personality repels her. (Doth the doctor protest too much?) Either way, she’s certainly not ready for Jasper’s non-reaction. It’s clear she wants credit for his growth and seems aghast at how much Lydia’s “fresh approach” has stolen her thunder.

When Adelaide’s self-portrait is attacked with red paint, Jasper shows up in place of his mother to answer questions.* The gallery owner Nolan DeMarco (Conor Donelan) was also splattered, and the attacker painted “PBD” on the wall. The acronym refers to an eco-activist group that Jasper is familiar with, as Cambridge students started it.

(*Again with the personal connections to cases. These plot conveniences are starting to feel more like contrivances. Do better, Season 5.)

This is a murder show, so a little vandalism isn’t where the story ends. The vandal strikes again, this time attacking DeMarco with the same paint and running away. DeMarco gasps for breath and collapses as if he’s been poisoned. He dies of “severe respiratory distress leading to a cardiac arrest.”

As with the first gallery attack, Jasper is struck by a strong smell at the crime scene and identifies it as paint thinner. Back at the precinct, the team discusses whether DeMarco’s death is suspicious. A forensics expert, Ken (Ian Targett), refutes Jasper’s claim that the paint was unusual. It was widely available and diluted with easily accessible acetone. Jasper ascribes motive to the use of acetone, but Ken dismisses it: “You don’t murder somebody by splashing them with paint.” Ken challenges Jasper’s certainty and authority, but Jasper won’t budge. He thinks DeMarco was allergic to acetone and that his medical record, which states no allergies, was falsified. Acetone allergies are rarely fatal, but a second exposure to an allergen within a short period could cause an immune system overreaction. Jasper is sure the two paint attacks were intended to kill.

The police investigate the PBD, which was founded by romantically involved students Henry Doyle (Merch Hüsey) and Dee Wallace. DeMarco was apparently a former member as well. Dee died years ago after a fall while resisting arrest; Henry was blamed for tipping off the police to her location. Even Dee’s mother, Anna (Renu Brindle), thinks Henry got Dee killed.

Blood found on DeMarco is linked to Henry, and when the police bring him in, there’s also red paint on his shoes. Henry claims seeing DeMarco interviewed on the telly solidified his suspicion that DeMarco turned Dee into the police. He admits he intended to kill DeMarco, but someone beat him to it. “I reached for a pulse, but he was dead.”

There’s a new angle when Highsmith discovers DeMarco was a former police officer under a different name. She meets with DeMarco’s covert ops handler, DSU Milton Droy (Chris Larkin), who claims not to remember DeMarco’s six-month stint and subsequent firing for petty theft. Droy is two days from retirement, a detail that will become important later.

Because nothing is a coincidence, Highsmith and Winters pick up protester and PBD member Jill Finch (Esme Hough), who was recently arrested and held at Droy’s station. She admits to throwing the diluted paint both times but seems genuinely horrified upon learning that DeMarco’s acetone allergy killed him.

However, Goswami has a gut feeling she can’t dismiss about Droy, who is retiring to a country without extradition. She sends Highsmith back to annoy Droy with questions about DeMarco’s medical records and which officers interviewed Jill during her arrest. She thinks there’s a connection between Droy, Jill, and DeMarco.

Finally starting to carve out her lane of usefulness, Highsmith’s attention to small details cracks the case open. She connects the dots between Jill and Dee’s mother Anna, realizing Jill was Anna’s foster child. Jill was deeply affected by Dee’s death, as was Anna, who was no longer able to care for Jill due to grief. Fed information on DeMarco’s role in Dee’s death, Jill learned of his acetone allergy from Droy, who called it “the perfect murder.”

Highsmith finds the smoking gun after they seize Droy’s files: DeMarco’s original medical record showing his acetone allergy, signed off by Droy. Though initially uncooperative, Droy corroborates everything after learning Jill has confessed it all. DeMarco was a lothario who got Droy’s daughter pregnant. She fell apart after DeMarco abandoned her and ended up in a “locked ward.” Learning of their PBD connection, Droy equipped and used Jill as a weapon of his revenge.

Back in the land of the love triangle, Peter and Zelda are on a fancy date where it’s clear he’s building up to the proposal. It’s just as clear she’s not interested. But before Peter can complete the task, Wilfred bursts into the restaurant to stop him.

The chemistry between Wilfred and Zelda is obvious. They talk about his proposal when they were young, and how Zelda is no longer afraid of love. She’s overjoyed when Wilfred presents the original ring and asks, “Take two?” She emphatically accepts his proposal. It’s an adorable scene.

But poor Peter! Zelda apologizes and informs him she would have said no. Ever the gentleman, he cedes the floor to the “better man.”

Do we get a season finale wedding?

• An emotional reckoning is coming for Winters that he continues to sidestep. The annual police fundraiser is dedicated to Lisa, and though he initially agrees to speak and even play music, he later backs out.
• Ms. Snares learns her friend Lyndon wrote a paper on the “warrior gene,” arguing for governments to eradicate those with the supposed aggression gene “in the womb.” This will apparently come into play in the finale.
• Wilfred is not Jasper’s father. At least not biologically. They share a sweet moment where the Dean reminds Jasper that in all the ways that matter, Wilfred was his dad.

Professor T Season 4 continues with new episodes on Sundays at 8 p.m. ET on PBS, the PBS App, and the PBS Masterpiece Prime Video Channel. All six episodes are available for members to stream on PBS Passport, as are Seasons 1 through 3. Season 5 has already been greenlit. Check your local listings.