'Betty White's Off Their Rockers' sneak peak: Old guy mistakes helium for oxygen

Betty White and the old people are up to their wily tricks again, as seen in this sneak peek from Wednesday's (April 11) episode of NBC's "Betty White's Off Their Rockers."

In the clip, an old man tricks an unsuspecting woman into thinking his tank of oxygen was swapped for helium, and it's about to explode. We're thinking had they actually made it explode -- like they probably would have on MTV's prankster show "Punk'd" -- it might have caused a very real heart attack for the oldster involved.

White, who was recently named the most liked Hollywood celebrity for the second straight year, hosts and executive produces the series, which airs Wednesday at 8 p.m. on NBC.