He acted in the English theatre in Bombay (now, Mumbai); he also appeared in Gujarati plays and in Hindi films and television.
He was part of the flourishing of drama in Mumbai in the 1970s and 1980s and 1990s and continued the long tradition of Parsi theatre in India.
[8] Hosi Vasunia grew up in Mumbai and attended St. Xavier's School and Sydenham College.
[7] An early appearance for Vasunia was in Princes (1970), a play written by Gieve Patel and directed by Pearl Padamsee.
Some years after Vasunia's death, he and Marzban were both remembered in the Hindustan Times as "two iconic Mumbai directors".
[18] The play returned to the Mumbai stage, a decade and more later, after the deaths of Amjad and Hosi, in a bilingual English and Hindi version.
Their first play was Don't Drink the Water, which was staged in 1979 and based on a script by Woody Allen; the production was directed by Pearl Padamsee.
[21][22] Although Vasunia was famous for comedy, he was responsible for "serious" theatre including such plays as All the King's Men (in which he was directed by Alyque Padamsee), Whose Life Is It Anyway?, Mass Appeal, Saint Joan, and Agnes of God.
The play, directed by Kerawala, was adapted by Bachi Karkaria from D. L. Coburn's Gin Game and was staged in Dubai, London, Antwerp, Dusseldorf, Paris, Chicago, and New York as well as numerous cities in India.
According to Bhawana Somaaya, the editor of Screen, "Yash Chopra had offered him roles in his various films but he didn’t take them up.
"[26] In 1989, Vasunia and Ronnie Screwvala founded the Dynasty Culture Club, which offered a range of entertainment such as theatre, cinema, music, and dance.
[26][29] Of his role in Never Too Late (1977), the drama critic of the Times of India wrote, "Hosi Vasunia is dominant as usual .
Don't underrate his talent: despite his sustained tempo and voice power, he is a master of modulation, a thespian of genuine artistic merit, a man with a look that can freeze you or make you roar.
"[30] In following year, the paper's drama critic, reviewing Cactus Flower, said Vasunia was "now the tallest giant of the English stage", and added, "You can't beat this guy at verbal pratfalls, double-takes, a voice with a marvellous range and tone, an utterly mobile face which conveys a thousand expressions (not all at once).
A reviewer of his female impersonation in Charley's Aunt said that Vasunia "strikes a delicious balance between high camp and inspired comic restraint".
The review added that while there were "unintentional lapses into his own familiar stage persona", the role was nonetheless "one of his best achievements".
"[39] Farid Currim remembered him as "one of the most unselfish actors on Mumbai's English theatre circuit" and recalled "the way he'd drive the audience crazy in terms of laughter".
[37] Alyque Padamsee spoke about his "joie de vivre, intensity and charisma", while Cyrus Broacha, who was given a career break by Vasunia in the play Brighton Beach Memoirs,[40] said that "he learned to embrace theatre as a community from his mentor".