Having a big-name star play the lead role in your movie is a big honour as well as a massive responsibility for any filmmaker.

“Thunivu” is the third collaboration between director H Vinoth and Tamil movie star Ajith Kumar, who is the standout of this action-packed film.

One could suspect that Vinoth wisely chose to let the veteran actor do what he does best. To that end, Ajith entertainingly chews the scenery in every shot he is in.

Indeed, one can tell the entire cast is having a fun time, with a few actors hamming it up all the way through.

If you are expecting a gritty crime thriller that takes itself seriously, “Thunivu” will clearly not be what you are looking for. It knows it’s excessive, and completely enjoys being so.

“Thunivu” focuses on a criminal gang planning a heist on a bank in Chennai. At first, everything seems to go as planned: the guards are subdued, the civilians taken hostage, and the cops held at bay.

Then, suddenly, a man with a white beard barrels his way into the picture, knocking out the bad guys holding the crowd at gunpoint.

A knight in shining armour, you might think? Not at all.

In the first of many surprising twists, this man played by Ajith – who is left nameless throughout – is there to rob the bank for himself, but his motivations are more complicated than mere greed.

Any good heist movie is at its strongest when it embraces the tropes characteristic of the genre, and “Thunivu” does this with relish, fierce gunfights taking place for most of its runtime.

Ajith’s anti-hero commanding the screen with equal parts of menace and humour. His character is unpredictable, capable of slapping someone at one moment and shooting them the next.

Meanwhile, actress Manju Warrier also gets to enjoy the ride in her role as Ajith’s sidekick, Kanmani, effectively the movie’s action lady.

To its credit, substantial amounts of social commentary are baked into the film, which doesn’t hold back when it comes to lambasting people in power.

From the banking industry’s unscrupulous practices to how politicians tend to exploit tragedies, the messages are overt but not overbearing; and thankfully, “Thunivu” doesn’t descend into excessive preachiness.

Of course, one issue that could be raised is that Ajith has so much star power, his character is effectively shielded from any danger.

Audiences will marvel at how this bearded man manages to survive non-survivable attacks on more than one occasion. Even in the final chase scene, he doesn’t stop firing at his pursuers when he has several bullets lodged in his shoulder!

The problem with this is, antagonists tend not to feel like much of a threat at all. If Ajith’s character can shrug off bullets, punches and stabs, what could they possibly do to stop him?

That said, the plot armour he wears may be over-the-top, but his character is still highly entertaining, oozing charm wherever he goes.

“Thunivu” moves at a rapid pace, leaving no time for the audience to breathe. This does tend to get laborious when twists and turns keep being thrown at you, so much so that it’s easy to lose track of what’s going on.

It certainly doesn’t help that there are banking terms aplenty, so the technical jargon might cause your head to get muddled even further.

The movie does seem to stampede towards its end, when slowing the action down every now and then would have worked to its benefit.

Still, at the end of the day, the entertainment factor of “Thunivu” trumps its flaws, thanks to its leading man’s charisma – and its overeagerness to embrace its ridiculousness.

‘Thunivu’ is screening in cinemas nationwide.