Was there ever a stronger season of series TV than the fifth and final season of “Angel?”

Okay, maybe you can make arguments for peak seasons of “Lost” or “Breaking Bad,” or going way back, the first season of “Star Trek.”

But the fifth season of “Angel” – in which the stalwart heroes of Angel Investigations are put in charge of Wolfram and Hart, the Los Angeles law firm that represents evil on Earth – has to rank right up there.

The first season or two of “Angel” – which debuted in October 2003 as a spin-off of “Buffy the Vampire Slayer” – were uneven, with real highs and lows as vampire-with-a-soul Angel moved from Sunnydale to LA and began fighting crime. The best episodes gave off a real Batman vibe, with Angel fighting evil by night, jumping from rooftops and traveling through tunnels under the city. The worst episodes made it seem like “Buffy” mastermind Joss Whedon didn’t quite know what to do with star David Boreanaz and his supporting heroes like Wesley (Alexis Denisof) and Cordelia (Charisma Carpenter).

But despite a few mis-steps, “Angel” gradually built to a stronger series that was not only about the supernatural forces at work on Earth but also the flawed heroes who stood between us and the demon world.

By the fifth season, “Buffy” co-star James Marsters had joined “Angel” as Spike, the charismatic “bad boy” vampire and antagonist to Angel. Everything clicked. Boreanaz and Marsters were almost co-leads and Denisof, J. August Richards and the lovely Amy Acker – joined later by Andy Hallett as showbiz demon Lorne – were as solid a cast as any show on TV in the 2003-2004 season.

By the episode “Smile Time,” in which the Angel gang took on demonic puppets – and Angel found himself turned into a puppet – the show had hit a perfect mix of drama, soap opera and character comedy.

Then Whedon – more recently writer/director of “The Avengers” – hit us hard in the heart with “A Hole in the World.”

For several seasons, Acker had been the series’ secret weapon. An adorable genius, Fred had been the object of affection of half the cast, including both Wesley and Gunn (Richards). By this episode, she had picked up another admirer, nerdy Wolfram scientist Knox.

Although the romance between Fred and Gunn had been dramatically interesting, Wesley and Fred were destined to be together. They finally realized their full romantic potential in “A Hole in the World,” and – true to the Joss Whedon School of Romance in Drama – were soon to be split asunder. It’s the old “fall in love, get hit by a bus” theorem that I’ve referred to before.

Fred is infected by spores from an ancient sarcophagus in the Wolfram lab. Very quickly, it’s determined – in a whipsmart scene in which Lorne, who reads people’s thoughts and future by hearing them sing, hears Fred singing a few notes – that Fred is dying inside as Illyria, an ancient demon, hellbent on returning to Earth, reshapes her as its vessel.

Wesley comforts Fred, Gunn over-compensates for his inadvertent role in Fred’s condition and Angel and Spike head for Great Britain to find the Deeper Well, a literal “hole in the world” from which Illyria sprang.

There’s a tremendous “band of brothers” feel to the group that works feverishly to save Fred’s life and Whedon not only writes a devastating finale to Fred’s story but elevates an already great season.

Because there’s a price to be paid for the hubris and ambition of the players in this story and Fred pays it.

What’s extraordinary about the story is that, even while it brings Fred’s existence to an end, it continues her story as Illyria and gives Acker a totally different acting challenge.

The fifth season of “Angel” continued to one of the best series finales ever, one that was perfect and satisfying and yet made you want more at the same time.

But the season peaked with “A Hole in the World,” leaving a hole in viewers hearts.