"Our Last Summer," includes the lyric "that was the time of the flower power," which is usually a reference to the late 1960s. In the same scene, Harry says he traded his Johnny Rotten tee-shirt to get a guitar for Donna. Rotten was a member of The Sex Pistols, which formed in 1975.
For at least 30 years, ABBA and their fans have sung "My my, at Waterloo, Napoleon did surrender."Napoléon Bonaparte retreated from Waterloo in June 1815, attempted to hold his army together for a month, then traveled to the European coast, where he surrendered to the British Navy.
As "Lay your Love on Me" transforms into Sophie's bachelorette party, cast members hold Sophie up and she drinks from a bottle, then throws it. After she throws it, they lay her on her back and her hair falls off her shoulders. In the following close-up shot, her hair falls off her shoulders again.
During "Take A Chance On Me", Bill appears to be standing directly under Rosie as she falls from the roof since he's looking directly above him. When Bill actually catches her it's clear that she is coming from the right side of the screen.
Tanya is barefoot when she gets out of the paddle boat. When she grabs her towel, she is still barefoot. Halfway through "Does Your Mother Know", she is wearing the same silver flats she wore on the dock when Donna pushed her into the water.
When Sam is singing "When All Is Said and Done " to Donna, he starts out with his sports-coat on and you see the end of the coat sleeve when he reaches to caress Donna 's face. However when the camera shows him singing, he is only wearing his dress shirt and his cuffs are rolled up.
During one song, an extra is up a ladder, which is pulled out from underneath him, leaving him hanging from the window ledge. In the close-up, a safety wire is visible, going out of his clothes and up into the window.
When Sam, Bill, and Harry first arrive at the Villa, they all seem known about Donna's daughter. Later, before "Dancing Queen," Donna says she never told any of the men about Sophie. We can assume that Sophie's name was on the invitations.
When Donna refers to herself as a "bigamist", she is referring to the fact that she would be marrying a man who, in the eyes of the Catholic Church, is still spiritually married. Event though legally divorced, the Catholic church would consider him still spiritually married until either the death of his ex-wife ('Til death do us part) or if the church grants an official annulment, which is a lengthy process. According to traditional Catholisism, a bigamy is considered both marrying two different people and/or marrying someone that is already married.
The goof items below may give away important plot points.
When Donna kisses Sam after she says "I do," she only has a ring on her pinky. After the kiss she puts the wedding ring on her opposite hand and kisses Sam again. Now the ring is still on her pinky, and another ring is on the next finger.