Keira Knightley, Olivia Colman, David Walliams and Idris Elba are among the stars to make an appearance in Comic Relief.
The fundraiser, which is being aired on BBC One, has raised a total of £25,406,076 so far, it was announced during the programme.
Knightley appeared alongside Carey Mulligan, Michael Sheen and Jodie Whittaker in a sketch for the programme.
The stars featured in a joke trailer for the film 2020 The Movie, which also featured appearances from comedian Matt Lucas, singer Gary Barlow, actor Sanjeev Bhaskar and YouTuber KSI.
Justin Bieber. Actual @justinbieber. On #RedNoseDay. pic.twitter.com/tFUGX7pJNI
— Comic Relief (@comicrelief) March 19, 2021
Justin Bieber also gave an exclusive performance of his song Hold On during the programme.
Comedian Jack Whitehall also hosted a Comic Relief Zoom call with Elba and Colman.
The programme is being presented by TV presenters Davina McCall and Paddy McGuinness, comedian Sir Lenny Henry and singer Alesha Dixon.
Comedian Dawn French opened the programme as her character from The Vicar Of Dibley as she sang Lizzo song Juice.
Welcome to your #RedNoseDay.
It's the Vicar of Dibley like you've never seen her before. The one and only @Dawn_French is lip-syncing to @lizzo for #RedNoseDay! pic.twitter.com/pwT5ShgLpo
— Comic Relief (@comicrelief) March 19, 2021
During the programme, comedian and children’s author Walliams joined Sir Lenny to meet schoolchildren, who were discussing the recyclable red nose being sold for Red Nose Day.
It was also revealed during the programme that double amputee racing driver Billy Monger raised £2,376,183 for Comic Relief.
Monger, who previously completed a 140-mile triathlon-inspired challenge for the charity, was told the fundraising total by the presenters.
He said he was “speechless”, adding: “That’s completely out of what I thought was possible, so thank you everyone.”