Manchan Magan made a trip around Ireland speaking only Irish to see if census claims of 1.6m people being able to speak the language were true on the ground.
Of those claiming to speak Irish 165,000 live in the north.
In the course of his travels Manchan gets kicked out of bars, served the wrong food, given the wrong directions, the wrong clothes, the wrong haircut.
"Seeing those figures I thought it should be very simple just to make one's way around," he told BBC Radio's Good Morning Ulster programme.
He met with a mixed response making the four episodes of No Bearla - No English - for TG4 - the Irish language broadcaster.
But while the level of fluency may not have matched the claims, it prompted strong feelings.
Accompanied by a film crew using a hidden camera a shopkeeper in Dublin covered his ears and told him to speak English or get out.
But why the hostility? Manchan said after 10 years of being schooled in Irish, people in the Republic may feel ashamed that they cannot speak the language.
"In some ways if you are speaking Irish some people will think it's a weapon of war, or they will think you're just showing off," he said.
His journey took him to Belfast and he said there was "great enthusiasm" for him using Irish on the Falls Road.
He then took his no English mission to the nearby Shankill Road, a staunchly loyalist area.
"I was met at first with bemusement - a few people talked to me in English saying that it was a sweet enough language as long as it wasn't shoved down their throats," he said.
"But then I was warned eventually that if I did insist on speaking Irish on the Shankill that I was liable to end up in hospital very soon.
"So I decided to shuffle off somewhere else after that and went to Letterkenny where I got a great reaction."
He said that there seemed to be a different attitudes among the generations towards the language.
"Younger people seem to be a lot more up for the language, willing to understand me," he said.
"In Dublin maybe it's just too fast paced to be listening to someone in another language."
He said that in the course of making the programme it was the rising number of ethnic minorities who made the most effort to accommodate him.
"It was actually the foreigners all over Ireland, the Chinese and Polish people in particular who tried to make an effort to understand me," he said.
They say the great test for language is whether you dream in it, and for Manchan his sleep is peppered with English not Irish.
"For probably the first 16 years of my life I would have been dreaming in Irish, but it's an English world and so one way or another we have to shift," he said.
He said that he would be very sad to see Irish die out as a language, and he was not alone.
He said three people on the Shankill said they did not want to see it go they just "didn't want it shoved down their throats".