Before Benegal began making feature films ('Ankur' was his first) - he was making commercials and documentaries for corporations and government bodies. 'Manthan', which immediately follows 'Nishant', is what would today be called a 'docudrama'. If in 'Ankur' he showed that it was perfectly possible for an oppressive socioeconomic system to arrive at an equilibrium where people are, more or less, happy where they are (the deaf-mute landless laborer symbolizing powerlessness in a, well, rather powerful way) and if in 'Nishant' he asks whether violent revolt was in fact likely to usher in a socio-economic order preferable to the one it displaces (also suggesting that the answer is 'no') - then in 'Manthan' he examines an attempt to bring about social change nonviolently - and inclusively - through an international institution-funded team of specialists. He moves the scene both in space and in time - from the Nizam's Hyderabad in the 1940s to the post-independence state of Gujarat, sometime in the 1960s; and now, instead of grain farmers, he looks at an entire village of dairy farmers.
The milk produced by the farmers is sold to a dairy processing plant owned by a 'capitalist' bad guy, played again with distinction by Amrish Puri (he was the landlord in 'Nishant'). The female lead is played by Smita Patil, who debuted in 'Nishant'. Clearly unafraid of irony, Benegal casts Patil, whose very surname connotes 'upper caste village headman' as a lower caste woman in 'Manthan'. And gives her a significant speaking part, which she didn't have in 'Nishant'. Girish Karnad returns as the leader of the team of specialists, as does Naseeruddin Shah, now cast as a 'half-caste'-but-treated-as-lower-caste male, perpetually scowling, alienated from the locals and deeply suspicious of outsiders (he was the landlord's youngest brother in 'Nishant'). Anant Nag (who also debuted in 'Ankur', along with Shabana Azmi) returns as a junior specialist in Karnad's team. Shabana Azmi herself is off working with Satyajit Ray at this time in Shatranj ke Khilari, having become famous through 'Ankur' and 'Nishant' - and does not appear in 'Manthan'. And in what appears to be an inside joke, Anant Nag's character in 'Manthan' is called 'Chandavarkar'. (Benegal, Karnad, and Nag(arkatti) are all Chitrapur Saraswat Brahmin surnames, as is Chandavarkar.)
One sees through Benegal's lens that, even when land is removed as the primary means of production, and replaced by cattle, serious social stratification comes to exist in the village. While both upper and lower castes own animals, the upper castes own more of them, control access to credit, and have significantly more power in the village. Importantly, they do not intermarry with the lower castes. It is often said in contemporary debate about Indian sociological trends that caste is the basic unit of social mobility in India, not the individual. One learns and relearns this basic sociological 'stylized fact' through the various situations Benegal creates in 'Manthan'. Benegal's focus on the patriarchy remains, and he uses the character played by Patil to demonstrate how the capitalist and powerful rural upper castes collude to oppress the lower castes, and in addition, how lower caste males further oppress the lower caste female. It is normally taken as an accepted fact that caste (or race) hierarchies invert the traditional gender hierarchy - i.e. if white (or upper caste) females are oppressed by their patriarchies, then lower-caste (or black) females are relatively more powerful relative to black (or lower-caste) males. Benegal shows that this need not always be so.
'Manthan' literally means 'churning' - as in churning buttermilk gives you butter (which the dairy actually makes). It also epitomizes the basic theme in the movie - that even the best attempts of specialist outsiders to create non-disruptive positive social change - results instead in a significantly agitated local situation, ripe for ferment. 'Manthan' is also an extremely evocative mythological trope. In Hindu mythology, the Gods and Demons together churn the ocean of milk for the elixir of immortality (amrit). The churning of the ocean (samudramanthan) also yields the Kalpavriksha (the wish-granting tree) and Kamadhenu (the mother of all cows, who could also produce any amount of milk the owner desired). While the Gods and Demons must together churn the ocean, the Gods have actually conspired to be the sole recipients of the amrit. This theme is played out in the movie both in the large and the small - one group (the upper castes) routinely attempts to co-opt the other (lower castes) in the 'cooperative dairy farm' that the specialists visualize, but attempts also to keep the benefits only to themselves.
In actual fact, the cooperative dairy movement in Gujarat not only caught on and took off - the Amul Cooperative Dairy became a vastly successful commercial operation, that, among other things, also blazed new trails in commercial advertising and copy writing. By the late 1970s, Amul and the milk cooperatives were successful enough that 'Manthan' could be funded by its lakhs of dairy farmers. It was the vision of Dr. V. Kurien, who, interestingly enough, is a Michigan State-trained mechanical engineer, that is largely responsible for the 'Anand miracle'. The character played by Girish Karnad appears to be loosely based on Kurien, and the movie itself is a tribute to the Anand miracle.
Apart from Naseeruddin Shah, who positively excels as the ever-suspicious, perpetually alienated, always scowling, 'half-caste' male, and Amrish Puri as the bad-guy capitalist, Kulbhushan Kharbanda does extremely well as the upper-caste village headman (the Patel). I was pained to find that Shah's fine performance went formally unrecognized - he garnered no awards or nominations for his acting - which, apart from being excellent in itself, also critically anchored the movie. He also mastered the rural Gujarati dialect local to the area, which adds much realism to both his performance and to the movie. (By contrast, Amrish Puri, cast as 'Mr. Mishra', delivers his lines in a very inauthentic-sounding Punjabi accent!).
Benegal ends 'Manthan' on an ambivalent note. Attempts by outsider well-wishers to initiate positive social change run up against local hierarchies in collusion with capitalist interests; yet, the very process of inducing change creates a churning (the manthan of the movie title) that results in a situation ripe for ferment. Benegal's lesson for development specialists appears to be: positive change has to occur from within, but your efforts, if well directed, can create enough 'churn' to tilt the possibility of success in your favor.