Ludwig Solves an Unsolveable Case in the Season’s Penultimate Episode

How do you solve an unsolvable puzzle?

That’s the case Ludwig is trying to crack in Season 1’s penultimate episode. Ludwig and Carter are called to investigate the apparent suicide of a private school headmaster, Mr. Durose (Christopher Parramore). The case resonates with Ludwig because it’s where he went to school, and his beloved math professor, Mr. Todd (Derek Jacobi), is still on staff. 

Even Carter doesn’t think it’s an open-and-shut case this time. For one thing, the headmaster’s typed suicide note is riddled with grammatical errors. For another, the desk the headmaster allegedly stood on before hanging himself is in perfect order—not a piece of paper out of place. “If it was a murder, then how did the killer get out? The windows are painted shut, and the door is locked from the inside,” Simon wonders.

If the key were still in the lock on the inside, it would have been impossible for someone to murder him and then leave the office. Or was it? The main suspect is Mr. Bishop (Sam Swainsbury), the school’s sport master. He had a beef with the headmaster over a couple of things. His star rugby player, Isaac Upton (Frankie Minchella), was caught smoking marijuana. The student tells Ludwig it was only half a joint. “Doesn’t make it half legal,” Ludwig responds. Mr. Bishop didn’t want that fact to go on Isaac’s academic record because he was on track for a scholarship. 

Also, Mr. Bishop was accused of an inappropriate relationship with a student. But he couldn’t have killed Mr. Durose (or so he claims) because he was away all weekend in Scotland on a solo trip. His girlfriend, Ms. Chordwell (Rose Ayling-Ellis), is also a Deaf teacher. (This fact will become important later.) The couple fought before he left (she’s the one who caught Isaac smoking a joint). Surprisingly, just before returning from his trip, Mr. Bishop proposed to his girlfriend via a video message.

Ludwig is distressed that his beloved math professor now falls asleep on the job, gets puzzles wrong, and has been demoted to housemaster. He wonders what happened to him. “Nothing happened. He just got 30 years older, that’s all,” Carter tells him. But Ludwig thinks he sees his bleak future in the professor’s current life—no family, no spouse. “Nothing else to come home to every night,” Simon says. Flashbacks show how the professor helped Ludwig as a student, protecting him from bullies and introducing him to puzzles and the idea of designing puzzles. You start with a solution and work backward. The key to a good puzzle is to have a few false paths “deliberately layered in,” he tells him. 

Mr. Bishop gets a little cocky with Ludwig, believing there’s no way he can be caught. (Clearly, Mr. Bishop hasn’t seen Episodes 1 through 4!). “It’s very awkward for you, isn’t it? That door being locked from the inside,” he smugly says to Ludwig. Ludwig goes to see his professor and asks how the killer could lock the door from the inside and then leave. Mr. Todd says the killer didn’t. “If a solution is impossible, it’s impossible by design,” he tells his former student. 

Lucy and Henry realize James’ phone has been hacked. Henry tells his mom he might have a way of tracking where Ludwig’s mysterious phone call at the end of the last episode came from. He only asks that his mom “not make a big thing about” how he knows how to do that. (He may or may not have used his computer skills to send a taxi every hour to his geography teacher’s house). 

Henry traces the number to someone named Botley, who lives in Wales. Lucy claims the name doesn’t sound familiar, but Henry doesn’t believe her. He hides in the back seat of Lucy’s car, and Lucy doesn’t even realize he’s there until she gets a call from the school wondering where Henry is. Lucy confesses that the name Botley is Matt’s wife’s maiden name. (Matt is James’ former partner.) It does not go well when Lucy arrives at their doorstep in Wales. “You need to leave now,” Matt’s wife tells her. She’s cut off before she finishes the sentence, but the implication is before she gets them all killed. 

And now it’s time for this week’s dramatic reveal! Ludwig gathers everyone in the headmaster’s office. He announces that it is Mr. Bishop who killed the headmaster by hiding out in his office all weekend after he had killed him. The door locked from the inside with a key was “a false path deliberately layered in.” Ludwig’s proof is two-fold. There’s a fresh apple core in the garbage can. It’s not brown as it should have been if the headmaster had thrown it away. More importantly, in the video message Bishop sent his girlfriend, the school bell tower ringing at 10 a.m. could be heard. His girlfriend wouldn’t have heard those sounds, but everyone else could. Bishop claims the talk of his inappropriate relationship with a student is just a rumor. “One doesn’t tend to kill over rumors,” Ludwig tells him. 

Before he leaves, Ludwig says goodbye to Mr. Todd, who has one question for Ludwig: “Why are you pretending to be your brother?” he wonders. Ludwig asks how he knows. “Think I don’t know my students,” he replies.

Ludwig is still trying to figure out why Holly covered for him and didn’t report that Ludwig was using Ziegler’s login to get into police records. “Are we really going to keep pretending like nothing happened between us? The Christmas party. You kissed me, remember?” she tells him. Simon overhears this conversation. 

But fret not! It doesn’t seem like James cheated on Lucy. More like this was Holly’s way of figuring out if James is really James. As the episode ends, Lucy gets a call from Holly asking her to meet her. “It’s about James. Please come,” she says ominously. 

Ludwig continues with one new episode every Thursday on BritBox. Season 2 is already greenlit.