The Point stars Caerphilly-born TV presenter and actor Matt Johnson, who plays the younger brother of a man who is convinced he does not want to live anymore.
The film will be shot in the Brecon Beacons, near the home of its scriptwriter Jasper Warry.
Mr Johnson is an active ambassador for the mental health charity Mind.
He recently presented the documentary Iselder a Fi (Depression and Me) discussing his own personal experiences with depression for S4C.
As well as appearing in The Point, he will also be the executive producer.
He said the script was "one of the best he's ever read".
"It wonderfully tackles the hugely important issues of mental health in a distinct, moving and humorous way."
Mr Warry said he was "made up" with Mr Johnson's involvement and hopes to start shooting in November.
He said they will be using local talent wherever possible, both in front and behind of the camera.

Wick Joint Campus is being constructed to replace Wick High School and Pulteneytown and South primaries.
It will also have community facilities which will be available to the public.
Highland Council said its contractor Hub North Scotland (Wick) Ltd had informed it of delays affecting the completion of the site.
The local authority said: "Regrettably it seems unlikely that the campus will be ready to open in October, as envisaged.
"Highland Council intends the best facilities possible for children and staff, and will not accept these buildings until work is completed.
"The council is working with the contractor to determine what the earliest possible date is for completion of the whole Wick Joint Campus project, and will make further announcements as soon as possible."

The 24-year-old, who played 16 games on loan at Kilmarnock last season, will compete with James Tavernier.
Hodson started his career at Watford and played 51 games in three seasons at MK Dons after a loan at Brentford.
He joins new faces Matt Gilks, Clint Hill, Joey Barton, Niko Kranjcar, Jordan Rossiter, Matt Crooks and Josh Windass at Ibrox.
Rangers paid an undisclosed fee for Hodson, who was part of Northern Ireland's squad at Euro 2016, but did not feature in any of their four matches.

England's win over South Africa on Sunday secured the Twenty20 series.
The game was officially sold out, as were England's two ICC Champions Trophy matches at the SSE Swalec Stadium.
The near-15,000 crowd comes as counties bid for the next round of five years' worth of international games.
"To have three full houses over 19 days for England matches is something we've very proud of," said Morris.
Cardiff hosted England's win over New Zealand and semi-final defeat to Pakistan in the Champions Trophy, along with Sri Lanka versus Pakistan and the less well-attended Bangladesh v New Zealand match.
Around 3,000 seats were not occupied for the England v New Zealand match because of poor weather forecasts, while cancelled trains are believed to have contributed to some empty seats for the T20 on Sunday.
But a rapid re-allocation of tickets worked well for the England-Pakistan game after fears that India supporters, who bought tickets for both semi-finals, would not turn up.
"It's particularly important (to have big crowds) this year, because at the back end of the year we are likely along with other counties to be bidding for our international programme between the years 2020 and 2024," explained Morris.
"There's also the new city-based franchise T20 as well, so it's important we can demonstrate we can fill houses and people have a great time when they are here."
England's score of 181 in 20 overs against South Africa could also come as a relief, after captain Eoin Morgan criticised the use of a previously-used wicket for the Champions Trophy semi-final, a choice attributed to the International Cricket Council.
"I wasn't surprised (with the score), it's a wicket that has played extremely well this year in domestic and international cricket, in recent years we've had some very good marks," said former county captain and England opener Morris.
Glamorgan have forecast an operating profit for 2017 on the back of five days of international cricket.
But it appears unlikely they will add another overseas player to their squad for the T20 Blast, after signing South African paceman Marchant de Lange on a three-year deal for all forms of cricket.
A Welsh feature film which tackles mental health issues is due to be shot in Powys later this year.
[NEXT_CONCEPT]
A new £48.5m school campus in the Highlands is unlikely to open in October as planned, Highland Council has said.
[NEXT_CONCEPT]
Rangers have made right-back Lee Hodson their eighth summer signing on a three-year deal from MK Dons.
[NEXT_CONCEPT]
Glamorgan chief executive Hugh Morris says Cardiff's third sell-out for an England match in June will boost their hopes of attracting further international matches.