What an intense episode of Terriers.

Many shows make the mistake of using flashbacks as nothing but a gimmick, revealing very little about characters and simply assuming viewers will be happy with the mere idea of going back in time.

But "Sins of the Past" gave us the answer to a pressing question - why did Hank's marriage fall apart? - while tying that storyline into present day events and character developments. It was yet another outstanding outing for what long ago stopped being the best show no one is watching, and started to come very close to being the best show on TV. Period.

Simply gut-wrenching performances by three of the show's leads this week.

Donal Logue almost exploded on screen drunkenly yelling at Gretchen while these two were married; Michael Raymond-James caused me to gasp at loud at the venom he depicted in beating up the man he thought Katie slept with; and Laura Allen broke my heart saying goodbye to Winston.

While the show made a mistake choosing its name, loyal viewers are well aware of where Terriers came from.

Britt and Hank and both men that cannot let a problem go. This serves them well as persistent private investigators. Once they sink their teeth into a case, they don't stop until it's solved. But the same attitude often causes major problems in their personal lives.

We've seen how that's been an issue for Hank, whose company both Mark and Gretchen obviously still enjoy, but who is simply not trusted by either - and we're starting to see how it might soon affect Britt. Can we blame the guy for going off at Katie's infidelity? Not really. But we can also see how his violent stubbornness is making it impossible for him to think clearly.

I say it every week, but no show combines quick, witty banter with gritty character portrayals and interesting cases like Terriers. Sadly, it barely averages 500,000 viewers per week, which is a paltry number for any network. I'm praying FX realizes what a gem it has on its hands, finds a new marketing scheme and gives this show a second season.

If it fails to, however, only two episodes remain. I've seen them both, they tie up the show's larger story arc and I can't recommend them strongly enough to viewers. If Terriers does go out after just 13 episodes, it will have been a terrific ride.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.