The blood factor of Signature Theater’s hilariously demented The Lieutenant of Inishmore makes the red pageantry of Tim Burton’s recent Sweeney Todd adaption star to feel almost as tame as an adolescent-run Haunted House.

Here, though, the spattering is played much more for comedic effect and sheer gross-out factor than artistic impact. And what it achieves is incredible, sick fun.

Credit the deft direction of Jeremy Skidmore (along with the fact Karl Miller makes for a strangely sexy sociopath) for fully realizing the potential of Martin McDonagh’s macabre masterpiece. Skidmore consistently achieves an off-kilter tone for the production, where brutality is sudden enough to shock, but much more often delivers a laugh than a shudder. And when you think the absurdity has wrapped up for good, the play delivers an extended coda that transcends everything seen so far.

The play’s catalyst is a seemingly mundane event: a dead cat found on the side of the road. Turns out this feline is the only friend of a mentally unstable domestic terrorist (Miller), who has entrusted it in the care of his father Donny (John Lescault) while he’s off bombing buildings and torturing drug dealers. Donny and Davey (Matthew McGloin), the kid unfortunate to have found Wee Thomas bleeding on the side of the road, can only imagine what the nut case will do when he comes home and sees what happens.

Skidmore’s assembled a cast who are all on the same page in achieving the work’s deadpan feel — Tim Getman, Michael Glenn and Joe Isenberg are a great comic trio as three terrorists who have it in for Miller’s Padriac. Miller, an exceptional actor who could probably manage complexity playing Mickey Mouse, here is uneasily off-balance and somehow still alluring and pitiable. Even a live cat that makes a key appearance in the play actually earns the curtain call he gets.

The Lieutenant of Inishmore runs through Nov. 16 at Signature Theater. Tickets are available online.