It seems like forever ago now, but Dexter, the Showtime drama with a morally ambiguous serial killer as its protagonist, was once in the conversation about television’s greatest shows. Bloodier than just about anything else on cable and featuring a magnetic lead performance from Michael C. Hall, for its first four seasons the series provided a masterful example of tension-wracked, episodic storytelling.

Then it promptly fell the hell off.

After a great fourth year that saw a season-long game of mental cat-and-mouse between Hall and nightmarishly creepy guest villain John Lithgow culminate in the sudden, surprising death of a major character, it seemed as though the show was on track to resolve itself in a taut five seasons, and end as one of the more notable programs of the aughts. Instead, Dexter basically reset, then went on autopilot. Season five was astonishingly uninspired. Last season showed glimmers of a slight return to glory early on before falling back on its rapidly curdling formula. At least it ended with the only cliffhanger the show has left — Dexter’s cop sister Debra (Jennifer Carpenter) walking in on him mid-murder — but even that felt desperate.

There’s still time for redemption, though. Dexter’s seventh season — it’s second-to-last — starts on Sept. 30. That gives the producers more than a month to implement the following suggestions and, almost surely, save the show from itself:

No more guest serial killers With Deb finally encountering her brother’s “dark passenger,” it’s time to pull the show as far away from its own clichés as possible. Unless Lithgow’s Trinity Killer rises from his watery grave, having yet another outsider with a famous face slaughtering the citizens of Miami is just dull at this point.

Resurrect Mos Def, somehow Speaking of rising from graves, the best thing about the last season of Dexter was Def . . . sorry, “Yasiin Bey,” as the reformed criminal Brother Sam. He reinvigorated the show with a nuanced, internalized performance before getting killed off after a few episodes. His death was pretty unambiguous, but who cares? Dexter isn’t so dedicated to realism that he couldn’t just reappear one day and say something like, “Uh, no, I didn’t die, I just needed to get out of town for a few days.”

More Masuka He’s the minorest of Dexter’s minor characters, but the delightfully pervy forensics investigator, played by C.S. Lee, is the show’s humor and, I’d argue, its heart. (He’s also the only member of the supporting cast who isn’t boring and/or annoying.) I’m still holding out hope for an eventual spinoff called Masuka After Dark.

Bring back Doakes Obviously, Dexter’s biggest problem is constantly smiting its best characters. In Season two — still the show’s best — the no-bullshit police sergeant discovered Dexter’s true identity, and got blown to bits for his troubles. My suggestion for getting him back on the show: He whacks Harry, the late father who appears to Dexter as an apparition, and becomes Dexter’s new conscience. C’mon, don’t tell me the show wouldn’t immediately get better just by Doakes yelling, “Kill that mothafucka!” every time Dexter experiences a moment of doubt. Writers, make it happen!

I Need Media is a biweekly media column. Matthew Singer watches everything from PBS documentaries to Community and Showtime’s Gigolos, but mostly he’s just happy Breaking Bad is back. Follow him on Twitter@mpsinger.