The idea is to use their reality and skeletons from the past to lend the ensuing hostility an air of authenticity and exasperation.

But to appreciate the ingenuity of this docudrama-style thriller, it’s important to know some history.

Nearly two decades back, Kashyap signed Kapoor to play the titular character in Allwyn Kalicharan. The 'jhakaas' hero even shot for its stylised neon-lit poster only to drop out last minute and leave Kashyap out in the cold.

Except, outside the industry or Kashyap's coterie and committed fan club, this is not a big deal.

Not like Shekhar Kapur's Time Machine or Mukul Anand's Dus, the epics that never saw the light of day, anyway.

In AK vs AK though, Allywn Kalicharan's resentful ghost haunts the proceedings, which kick-start with a public spat after one calls the other 'invisible, irrelevant' only to be countered as 'industry ka sabse bada fraud'.

You can easily imagine who's who.

If not, there's a good chance, its wit ('Ek din ka chief minister apni beti nahi dhoond sakta/Anees Bazmee ka number <em<>deta hoon uske yeh line maar') will be lost on you.

By his own admission an experiment, Motwane;'s trippy film unravels from an industry insider's outlook.

The jibes exchanged are ceaseless and churlish, quite like the comments one reads under a celebrity's social media.

In the beginning, I wasn't sure in what spirit the movie wants to be seen.

The vibe is put-on.

The humour sounds farcical.

The bantering is too self-aware.

And the in jokes-club is strictly by invitation.

But as the plot thickens, AK vs AK becomes more about in-the-moment than an exercise in purpose or point.

Constantly accompanied by a girl rolling a camera, Kashyap -- the flagbearer of raw, real cinema approaches Kapoor -- the champion of masala on the sets of a movie where he is shooting against the green screen in the role of an air force officer.

Looks like his uniform ruffled the Indian Air Force's feathers enough to procure a disclaimer in writing and person insisting no disrespect intended. And it's not.

The entire focus is on Kashyap arm-twisting birthday boy Kapoor into a bizarre game of scripted reality, where he must find daughter Sonam who he has kidnapped and hidden in some secret corner of Mumbai in 10 hours.

'Jaggu ka idea lagta hai,' laughs Kapoor alluding to his co-star and chum Jackie Shroff.

On learning Kashyap's outrageous brainwave, in the artistic vein of David Fincher's Game, is no prank, Kapoor panics.

What happens next I will not reveal, but Motwane's rhythmic thriller is successful in giving an improbable scenario a grim solidity.

AK vs AK's real-time urgency benefits from its on-the-spur-of-the-moment impulses.

Reel and real struggle to stay apart as a star's vulnerability is relentlessly attacked for spectacle.

The show goes on once he puts on those sunglasses and embraces his duties as a performing monkey before a selfie hungry, starstruck crowd.

They made him. Now they want a piece of him.

On one hand, there are prejudices and perceptions, on another pretentions and posturing.

The journey from Kapoor's plush home and Kashyap's DVD piled walls and various Christmas celebrations strewn across the city acknowledge the degree of filmi in our blood.

In name-dropping the method acting standards of Stanislavski and Daniel-Day Lewis, in showering of F-words in ways Tarantino would approve, in the suppressed dreams of a cabbie, in the celebrity endorsement craving of folks in not-so-glamorous profession.

But it's when things get volatile, like the intense chase sequence across roads and railways, captured by Swapnil Sonawane, AK vs AK hits some high notes.

It's not always a smooth run, but there are some sneaky surprises in store as well as a post end-credits scene.

It may seem a tad too convenient, but how it answers the debate it started is significant: Who's bigger: The star? Or the director?

AK vs AK enjoys the best of both worlds.

Motwane's freehand touch enables his two splendidly secure leads to do their thing against a massively self-referential setting.

Anil Kapoor's mastery shows in how he finds the space between an actor reaching out to his actuality while remaining an actor while Kashyap's comfort in bullying his co-actor fuels their bickering camaraderie.