By James Hibberd
Updated July 08, 2011 at 04:04 PM EDT

The return of Big Brother delivered strong ratings for CBS, the veteran reality contest pulling down 7.7 million viewers and a 2.7 rating among adults 18-49.

That’s up 8 percent from last summer’s opener and marks the show’s best debut rating in four years. Brother returning didn’t help the show’s 9 p.m. ABC Expedition Impossible (5.5 million, 1.6) over on ABC, the adventure contest slipped again, down 16 percent this week. Lead-in Wipeout (6.6 million, 2.0) was flat while 10 p.m.’s Rookie Blue (5.6 million, 1.5) gained slightly.

On Fox, So You Think You Can Dance (5.4 million, 1.6) was unchanged from last week’s low.