While the gang is attending a Russia/USA hockey match, they stumble on another mystery: the frozen ghost of a former hockey player has stolen the Emperor's Cup trophy and is haunting the stadium.
This episode includes examples of the following tropes:
- Blue Means Cold: The monster, supposedly the ghost of a frozen hockey player, is blue-colored.
- Buy or Get Lost: When Velma follows one of the suspects to a tailor's, the owner comes out and snaps at Velma for loitering, saying she should only be around if she's a customer.
- Continuity Nod: Shaggy comments that between this hockey match and the wrestling tournament, they've been eating a lot of stadium food lately.
- Cramming the Coffin: The ghost chases the gang into Lenin's tomb, and Shaggy and Scooby hide in Lenin's coffin. They eventually realize where their hiding spot is and panic, especially when they can't force the coffin back open.
- Disproportionate Retribution: The ghost's backstory says that a hockey player missed an easy goal, costing the team the championship. In return, he was banished to Siberia and froze to death.
- Eat the Camera: The Cold Opening ends with the ghost headings towards the camera, mouth open as he growls.
- El Spanish "-o": When Fred is introducing himself to the security officers, he calls himself "Freddyski."
- Fictional Fan, Real Celebrity: Real life hockey star Brett Hull appears as part of the US team. Fred in particular seems to be a big fan.
- Hidden Depths: Velma turns out to be a hockey fan and geeks out first when the gang arrives and then when she gets to play goalie for a bit as a reward for solving the case.
- Improvised Weapon: Brett Hull uses a series of hockey pucks as missiles to scare off the Frozen Fiend when it attacks Shaggy and Scooby on the lake.
- Overly Narrow Superlative: When Velma needs to grab a pair of skates, she claims to be her country's premiere skater and then needs to backpedal after she falls down.Velma: ...It's a very small country?
- Pop-Culture Pun Episode Title: The title refers to the song "Diamonds are a Girl's Best Friend".
- Red Herring:
- A trio of USA hockey fans appear as recurring characters, and they say that they'd do anything to help their country win. None of them is the Monster of the Week.
- Nicolai, the leader of the Russian team, resembles the diamonds' original owner, is in the locker room soon after the Frozen Fiend disappears and gloats that the US team doesn't stand a chance after Brett Hull is arrested as the ghost. He's not the monster either.
- Tempting Fate: Shaggy comments that at least the Frozen Fiend can't attack people off the ice... moments before the villain comes straight for them as they stand outside the stadium.
- Verbal Backspace: Fred yells that they've got the ghost when he thinks they're about to trap him... but then the ghost leaps over their heads, causing Fred to correct himself.
