This Is Spinal Tap (1984)
The Scene: The Brits decide to stage the biggest show known to man for their epic rendition of 'Stonehenge'.
The Song: Sadly, the sets designed by guitarist Nigel Tufnel (Christopher Guest) are all created too small. Far too small...
Join In When: The need to rock overpowers your soul.
Casablanca (1942)
The Scene: "Play it, Sam," implores Ilsa (Ingrid Bergman), requesting a song from the pianist at Rick's CafÈ American.
The Song: Sam tinkles the ivories, playing 'As Time Goes By', prompting tears from Ilsa and anger from Rick (Humphrey Bogart).
Join In When: The sobbing stops.
Top Gun (1986)
The Scene: Maverick (Tom Cruise) wants to impress Charlie (Kelly McGillis) in a bar, so he grabs a mikeÖ
The Song: "You never close your eyes anymore when I kiss your lips," croons Cruise, kicking off a bar-full rendition of 'You've Lost That Loving Feeling'.
Join In When: The rest of the bar does.
Young Frankenstein (1974)
The Scene: Dr. Frederick Frankenstein (Gene Wilder) hits the stage with his monstrous creation.
The Song: The duo frolic about singing 'Puttin' On The Ritz', which is as hilarious as it is creepy.
Join In When: Whenever the Monster sings his lines – but only if you’re any good at impersonating him.
The Fabulous Baker Boys (1989)
The Scene: Susie Diamond (Michelle Pfeiffer) wears a red dress and drapes herself over a piano during a performance with the Fabulous Baker Boys.
The Song: Susie purrs the lyrics of 'Makin' Whoopie'.
Join In When: It's important that you don't - you don't want to ruin the moment, do you?
Monty Python's The Meaning Of Life (1983)
The Scene: A Yorkshire man returns home to his wife and hundreds of collected children, where the entire family sing a song about the fact that they're not allowed to use condoms because they’re Catholic.
The Song: 'Every Sperm Is Sacred', a musical number so funny it'll have you snorting with laughter.
Join In When: The wee ones start singing that titular line. How they got away with this, we've no idea.
The Man Who Knew Too Much (1956)
The Scene: Jo (Doris Day) and Ben (James Stewart) learn that their kidnapped son is at the Prime Minister's embassy in London...
The Song: The PM asks Jo to sing a song, so she sings 'Que Sera Sera' as loudly as she can - it's her son's favourite and if he hears her, he'll come running.
Join In When: The chorus kicks in and Day gives it her full emotional heft. We got chills.
Who Framed Roger Rabbit? (1988)
The Scene: Eddie (Bob Hoskins) goes to a club where Roger Rabbit's wife, Jessica, works as a singer. It's not long before she makes her grand entrance.
The Song: Jessica sings 'Why Don't You Do Right?' (voiced by Amy Irving) while making every heart in the room bleed.
Join In When: You've managed to pick your jaw up off the floor.
Back To The Future (1985)
The Scene: Marty (Michael J. Fox) is performing at the prom while still attempting to fix up his mom and dad.
The Song: Marty's given the mike to sing an 'oldie'. "Well, it's an oldie where I come from," he says, before playing 'Johnny B. Goode' and scary everybody silly.
Join In When: That infectious chorus comes along. "Go go! Go Johnny go go!"
Some Like It Hot (1939)
The Scene: Sugar Kane (Marilyn Monroe) is on stage at a fancy event, with Josephine (Tony Curtis) and Daphne (James Stewart) providing musical back-up.
The Song: Kane coos 'I Wanna Be Loved By You' in a way that makes you think she's talking directly to you and just you – nobody else but you. SWOON.
Join In When: Monroe milks the chorus for all it's worth.