The 'High School Musical' cast will reunite for a special 'Disney Family Singalong'.

The stars - including Zac Efron, Vanessa Hudgens, Ashley Tisdale, Corbin Bleu, Monique Coleman and Lucas Grabeel - will get together through the wonders of technology to perform 'We're All In This Together' via video link for ABC's one-off celebration of the movie on 16 April.

Filmmaker Kenny Ortega - who directed the 2006 musical - told Deadline: ''We couldn't reach Zac until late but when we did, he immediately jumped in, of course.

''Everyone we reached out to was quick -- and you'll see it in their spirit and the way they come together from their homes.

''They recognise this is an opportunity to strengthen spirits for those joining us for the broadcast.''

Kenny insisted the song itself has been an anthem of sorts during the coronavirus pandemic, with the lyrics providing some comfort to people.

He said: ''You're hearing those words chanted out -- I've been sent videos from doctors, orderlies, nurses and medical professionals in masks and hospital gowns singing 'We're All In This Together' in the hallways of hospitals.

''It's a really nice fun coming together of a lot of young people that are banding together under the lyrics of this song for the show.''

The director noted that actress Ashley sparked the idea of people filming themselves singing the tune - which was written by Matthew Gerrard and Robbie Nevil - and now the reunion performance can help people who needs some respite.

He added: ''These artists that have come together are heroes. There are young people out there that look up to these people and have for a long time.

''To see them in their own living rooms and in their sweatpants hanging out with their families helps everyone realise there's truth behind these words -- we're all in this together in various circumstances. We need to feel that company.''