Titus Welliver previews the final season of Bosch — watch the explosive trailer

There's no such thing as an open-and-shut case on Bosch, and the final season of Amazon's crime drama will find Titus Welliver's titular detective going to perhaps his greatest lengths yet in pursuit of justice.

As seen in the first full trailer — which EW can exclusively debut above — season 7 finds Det. Harry Bosch investigating an arson fire that claims five lives, including a 10-year-old girl and two mothers, one of whom is pregnant.

"So now you've got a murder case, but you've got kids," Welliver tells EW. "And as everybody knows, for Harry, that's where it gets to a place where it makes him really, really dangerous for bad guys. So his pursuit of that becomes relentless, as he does with all other cases."

As Bosch works the case, he realizes all too quickly there's something deeper and more sinister going on, leading him to tangle with the building's shady management, a local gang, a "female Stringer Bell," and other powerful forces. Meanwhile, his trusted partner J. Edgar (Jamie Hector) is in a downward spiral after his fateful showdown with his nemesis Jacques Avril last season.

Edgar's ordeal strains his partnership with Bosch, but it also deepens their relationship, "and hence the audience's relationship to them," Welliver says. "So I think that will be the big payoff, to see how they work their way through it, unpack that, and it's a lot of stuff. You know, while there is a healthy dose of action and things going on, I always feel like [Bosch] comes down to stories about people, and the fragility of human nature."

Elsewhere in Bosch's world, his daughter, Maddie (Madison Lintz), assists powerhouse attorney Honey Chandler (Mimi Rogers) on a high-profile case that carries its own risks.

Whatever happens in the final season of Bosch, though, viewers can rest assured they haven't seen the last of Harry. In March, Amazon's free streaming service IMDb TV announced a yet-untitled Bosch spin-off series that will star Welliver, Lintz, and Rogers.

"I shudder to call it a spin-off because it's really not; it's just the continuing saga of Harry Bosch," Welliver says. "He's in a different place, but it's a continuation… A lot is revealed toward the end of this final season of Bosch — I do air quotes on that, 'final season' — which lays the foundation for where we will find these three characters as we open the new show."

He adds, "I'm just looking forward to getting in there, and we start mid-June, so it's soon."

Season 7 of Bosch premieres June 25 on Amazon Prime Video.

Related content:

• Lance Reddick picks the perfect Fringe, The Wire, and Bosch episodes to binge
• Bosch teams up with Det. Ballard for the first time in Dark Sacred Night: Read an exclusive excerpt
• Actress Jasika Nicole on why she won't do any more cop shows: 'I want to turn my privilege into power' (Op‑ed)