Who's going to miss Mad Men more when it's gone: Mad Men fans, or AMC?

Sure, fans will be sorry to see the doors of Sterling Cooper & Partners close for good when the Emmy-winning drama airs its final seven episodes next year — but at least we have other shows to watch.

AMC, on the other hand, doesn't have a lot to fall back on, after losing Breaking Bad last year and striking out with a series of short-lived misfires. (Low Winter Sun, anyone?) Without mega-hit The Walking Dead, the network is dangerously close to going back to being that channel that just shows old movies again.

Maybe that explains Halt and Catch Fire, a sleek new attempt by AMC to replicate the success of Mad Men. It's another workplace drama set in the past (during the personal-computer boom of the early 1980s), led by a charismatic visionary with a murky background. But the formula works: Three episodes in, Halt still has a few glaring bugs, but it has promise, too, and makes for a decent summer fill-in for Mad Men fans.

Scoot McNairy and Lee Pace (Tina Rowden/AMC) More

Set in 1983, Halt centers on Cardiff Electric, a small Texas software company where swaggering executive Joe MacMillan (Lee Pace) has been brought in to help sell business software. Joe has bigger plans, though: He wants to take on the industry's 800-pound gorilla, IBM, by reverse-engineering their PC and making Cardiff's own version… only cheaper and faster. And he recruits deflated engineer Gordon Clark (Scoot McNairy) and young coder Cameron Howe (Mackenzie Davis) to build it for him.

[Related: We Chat With 'Halt and Catch Fire's' Leading Man, Lee Pace]

Like Mad Men, Halt revels in the period details of its early-'80s setting, making us nostalgic for the days of floppy disks and MS-DOS. (It's not afraid to throw in a borderline cheesy '80s-style montage, either.) And there's also a delicious dramatic irony to watching brilliant minds laboring to build a computer with a fraction of the processing power of the last phone you threw away. When Joe pitches "a truly portable computer with two disk drives, integrated screen and keyboard, weighing no more than 15 pounds," he gets laughed out of the room.

Just as Joe is trying to reverse-engineer an IBM PC, Halt and Catch Fire seems to be trying to reverse-engineer its own Don Draper with Joe. His impassioned speeches for innovation recall Draper's finest pitches, and while no one can fill Jon Hamm's shoes, Pace comes close; he's magnetic as Joe. But actually, between Joe's weird body scars and his lone-wolf existence (he lives alone in an immaculate '80s apartment, complete with mood lighting and glass-block walls), he's less Don Draper and more Patrick Bateman from American Psycho. (We wouldn't be shocked to see him hack someone to pieces with an axe to the sounds of Huey Lewis and the News.)

The other two leads are strong as well. You may remember McNairy as the hostage who pitched a sci-fi epic to Iranian officials at the end of Argo, and he's great here as Gordon, a meek pencil-pusher who rediscovers his verve for computing after teaming up with Joe. And Davis is compelling as Cameron, a punk-rock programmer who looks like the lovechild of Watts from Some Kind of Wonderful and Rory Gilmore. Together, they're a formidable trio with brain power to spare, and we can't help but root for them to beat IBM at their own game, just like we root for SC&P to beat out the big ad agencies on Mad Men.