LAST night’s Big Brother went off with a blast as Helen Wood got “killed off” by pal Ash Harrison.

The shopping task, entitled Assassins, saw three housemates get nominated to “murder” the others without detection.

Big Brother gave Ash a smoke bomb to plant behind the sofas and engineer Helen and Christopher Wright to sit there before detonating it.

The pair were successfully killed and sent to the morgue — where Helen couldn’t resist a peek under the covers to see just how life-like the corpses are.

The housemates can only pass the challenge when all housemates are killed without detection.

Meanwhile, ahead of this week’s eviction, the beauty salon owner is also worrying that her relationship with Ash is putting him at risk, saying: “I can’t be seen with him this week.”