'A Land without Magic' was seen by 1.21m (5.7%) on Channel 5 in the fairytale drama's usual 8pm slot, and added a further 180k (0.8%) an hour later on +1.
Rising around 400k week-on-week, the US show benefited from a crafty Channel 5 scheduling decision.
The Richard Desmond network's airing of family film Beauty and the Beast attracted 1.7m (9.6%) from 6.15pm and 213k (1%), 5's best rating of the day. Celebrity Big Brother mustered 1.41m (6.3%) at 9pm (+1: 183k/1.1%).
When including timeshift viewing, the audience made it Once Upon a Time's most popular episode since April 22.
Elsewhere on Sunday evening, Inspector George Gently anchored BBC One's lineup, as the detective drama returned for a fifth run with 6.14m (27.5%) from 8.30pm, sending ITV1's critically-acclaimed 9pm drama The Last Weekend crashing to 1.98m (8.8%) for its second and penultimate instalment - 196k (1.1%) caught it on +1.
Gameshows fared better on ITV, with Bradley Walsh's The Chase pulling in 3.15m (16.8%) at 7pm (+1: 151k/0.8%), and Chris Tarrant's Who Wants to be a Millionaire? taking 3.14m (14.7%) at 8pm (+1: 106k/0.5%).
Comedian Peter Kay continued to prove a draw for viewers on Channel 4, as a reshowing of his 2003 gig at Manchester Arena entertained 2.24m (10%) in the 9pm hour, and an impressive 552k (3.2%) on +1.
Disappointingly for Channel 4, however, Kay's popularity did not have the desired knock-on effect on Bad Sugar, a new sitcom pilot from the makers of Peep Show. Starring Olivia Coleman, the half-an-hour mining melodrama logged 710k (4%), signing out the broadcaster's Funny Fortnight season with a whimper.
Meanwhile, Exploring China: A Culinary Adventure (1.18m/5.5%) and Toughest Place to be a Ferryman (1.34m/6%) aired between 8pm and 10pm on BBC Two and BBC HD.
Overall, BBC One swept home the primetime crown with 25.4%, over double ITV1's 12% (+1: 0.6%). Channel 5 rallied to third place with 6.4% (+1: 0.9%), trumping Channel 4's 5.9% (+1: 1.9%), and BBC Two's 5.6%.
> Read our full ratings report for Sunday's multichannel TV here
BARB ratings data supplied by Attentional