Okay, so this is a filk to the tune of Fireman Sam. The filk comes first, and then the song it's based on.

When Sookie gives him a call,
Shifter Sam is there to maul
putting on his furry coat,
turning into dog or stoat

He's always at the Bar.
Shifter Sam!
With his changer skills bizarre.
Shifter Sam!
You cannot ignore, Sam is the hero next door.

Serving people in Merlottes,
as cat or fish or horse he trots.
Sookie could be in a jam,
so hurry hurry Shifter Sam.

So move aside, make way.
Shifter Sam!
'Cos he's gonna save the day.
Shifter Sam!

He's the one that we adore. Sam is the hero next door.

When fighting vampires,
he's always cool and calm,
and everyone admires,
when sookie gives alarm.
He's great, he never tires.
He always sees it through
and that's true.

So move aside, make way.
Shifter Sam!
'Cos he's gonna save the day.
Shifter Sam!
He's the one we adore.
Sam is the hero next door.

If your cat's caught in a tree,
Sam will climb and set it free.
If Sookie gives him a shout.
Sam will always help her out.

Hooray for Shifter Sam!
He's always brave and strong.
Hooray for Shifter Sam!
And when there's something wrong.

He'll always be along to help both you and me
Don't you see?

He's always at the Bar.
Shifter Sam!
With his changer skills bizarre.
Shifter Sam!
You cannot ignore,
Sam is the hero next door.

Everybody knows Shifter Sam.
With his cold, wet, shiny nose.
Shifter Sam!
Well, we've seen him before.
Sam is the hero next door.
So move aside, make way.
Shifter Sam!
'Cos he's gonna save the day.
Shifter Sam!
He's the one we adore.
Sam is the hero next door.
He's always at the Bar.
Shifter Sam!
With his changer skills bizarre.
Shifter Sam!

You cannot ignore, Sam is the hero next door.

Here's the original theme for comparison.

When he hears that fire-bell chime,
Fireman Sam is there on time.
Putting on his coat and hat,
In less than seven seconds flat.

He's always on the scene.
Fireman Sam!
And his engine's bright and clean.
Fireman Sam!
You can not ignore,
Sam is the hero next door.

Driving down the busy streets,
Greeting people that he meets.
Someone could be in a jam,
So, hurry hurry Fireman Sam.

So move aside, make way.
Fireman Sam!
'Cos he's gonna save the day.
Fireman Sam!
He's the one we adore.
Sam is the hero next door.

When he's fighting fires,
He's always cool and calm.
And everyone admires,
When there's a fire alarm.
He's great, he never tires.
He always sees it through
And that's true.

So move aside, make way.
Fireman Sam!
'Cos he's gonna save the day.
Fireman Sam!
He's the one we adore.
Sam is the hero next door.

If your cat's caught in a tree
Sam will climb and set it free.
If you're stuck give him a shout.
Sam will always help you out.

Hooray for Fireman Sam!
He's always brave and strong.
Hooray for Fireman Sam!
And when there's something wrong.
He'll always be along
To help both you and me
Don't you see.

He's always on the scene.
Fireman Sam!
And his engine's bright and clean.
Fireman Sam!
You can not ignore,
Sam is the hero next door.

Everybody knows
Fireman Sam.
Dressed in his fireman's clothes.
Fireman Sam!
Well, we've seen him before.
Sam is the hero next door.

So move aside, make way.
Fireman Sam!
'Cos he's gonna save the day.
Fireman Sam!
He's the one we adore.
Sam is the hero next door.

He's always on the scene.
Fireman Sam!
And his engine's always bright and clean.
Fireman Sam!
You can not ignore,
Sam is the hero next door.