Detective Byomkesh Bakshy! is spine tingling, hair raising, heartstopping and it plunges you into the euphoric trance that film buffs enter when they’re given the most potent cinematic fix.

Let’s first get the pink elephant out of the room – Detective Byomkesh Bakshy! is not for purists. If you’re a raging fan of Saradindu Bandyopadhyay’s classic character, you will find a billion things that don’t match. This Dibakar Banerjee film is a new take on the character. If you can’t accept that, exit this review and go back to your VHS tapes. For the rest, let’s get to the good stuff.

The opening scene of Detective Byomkesh Bakshy! is iconic. It’s 1942, a wintry Calcutta night. A boat moors along the coast. A pack of Asian people appear. One of them mentions, in Chinese, that it takes time to load 500kg of opium. A hooded figure emerges from the darkness, its shadow cast on the wall in a sinister outsize. The figure warns the Chinese that it wants Calcutta back and guffaws terrifyingly. Everyone’s throats are slit open.

It’s spine tingling, hair raising, heartstopping and it plunges you into the euphoric trance that film buffs enter when they’re given the most potent cinematic fix. Because at this point, you know you’re about to see something special.

After that, Banerjee cuts straight to the case. The chemical engineer father of Ajit (Anand Tiwari) has gone missing, so Ajit enlists the help of a certain Mr Bakshy (Sushant Singh Rajput). Often, a movie about a larger-than-life hero showcases the protagonist’s entry in a bombastic manner. Banerjee’s Bakshy, however, makes an unexpectedly subtle entry, playing carom and getting knocked in the face. It’s one of the several instances where Banerjee’s direction subverts your expectations in Detective Byomkesh Bakshy!.

There isn’t much time to waste and Bakshy gets cracking on the case. Clues begin flooding in and he begins zooming around Calcutta, sniffing at the trail they leave behind. Sure enough, a body turns up, as does a seemingly antagonistic femme fatale (Swastika Mukherjee) and Bakshy and Ajit find themselves neck deep in a deliciously seedy conspiracy.

The film’s storytelling style is pure unbridled sex with the camera. Every clue is a thrilling experience, dragging us deeper into the murky mystery with Sneha Khanwalkar’s insane industrial death metal music. Your jaw will remain on the floor for most of the runtime because at any given instance, there’s always something leaping out to dazzle your eyes. Every frame of every scene has an insane amount of intricate detailing and it brings a pre independent Calcutta to life.

At certain times the film even shows off the gorgeous production design, like during the opening credits when the camera slowly shows us poster-clad Calcutta streets through a tram window. The intoxicating visuals are complemented by the breakneck pace of the case, which together make the 150-minute runtime seem like a cool breeze on Howrah Bridge.

The question on a lot of people's minds would be if Detective Byomkesh Bakshy! borrows any elements or style from Guy Ritchie’s Sherlock Holmes or its BBC counterpart. Fortunately, it doesn’t. Banerjee’s is neither an action movie nor a tale of an unstoppable super genius. His Bakshy detective is refreshingly human and grounded, despite being a Bollywood hero. His ‘heroism’ exists on a level that’s midway between Rajit Kapoor and Benedict Cumberbatch. It’s a tough balance to pull off, considering Bakshy is up against Samurai tuition teachers, Japanese drug lords from Shanghai and a mysterious figure that is more dangerous than either of them. So Bakshy is beaten, both physically and intellectually. This is his first big case and the rust and vulnerability are on full display.

Slipping seamlessly between shyness, good-natured cockiness and enthusiastic charm, Rajput is a fun Byomkesh Bakshy. Frequently, he underplays the character, letting his costumes and unibrow do the work. Banerjee has no doubt refined Rajput’s quiet, soft-spoken presence into a likable and offbeat acting style. Rajput has his showreel moment in a scene in which he gets high and unlocks a puzzle to the mystery.

Beyond the hundreds of plusses in the film, there is a shadow of a minus. The third act of the film will forever be the subject of bickering and argument between those who have seen the film. It’s not that the finale is disappointing, but there is a certain dependence on red herrings and it feels frustrating. It’s really hard to describe what goes wrong without going into spoiler territory, but something huge happens halfway and in the third act the film leads you to believe it’s more than what it is, when it actually isn’t.

What makes it stranger is that the final few minutes go into over-the-top masala Bollywood territory, totally out of place with the tone of rest of the film, which is beautifully restrained. No matter how you look at it, the disappointment at the ending is very hard to shake off once you leave the theatre.

Another aspect that falls flat is the femme fatale of Swastika Mukherjee, who makes the worst Bollywood debut since Nargis Fakhri in Rockstar. Most of her seduction is unintentionally hilarious at best and her big, dramatic moment only hurts the film at its weakest point. Fortunately she’s balanced out by the rest of the excellent cast, including Neeraj Kabi, Divya Menon and particularly Tiwari as the sidekick who literally kicks down doors with his side.

What’s wonderful is that you absolutely do not have to be familiar with the old cases of Byomkesh Bakshy to enjoy this film. It’s perfectly calibrated for both old hats and newcomers. It renders a bit of pop culture to today’s audiences – after all, we’ve never really had an adventurer in desi cinema.

Detective Byomkesh Bakshy! is ultimately a wicked cocktail of clues, images, sounds, emotions and sensations. From start to end, you’ll be firmly affixed to the edge of your seat. Hopefully this is the start of a franchise and the dawn of a bold new era for Yash Raj Films.