Mel C, Jack Dee, Dara O'Briain and co's dangerous trek down the Zambezi river attracted 4.71 million (20.7%) at 8pm.
Afterwards, the second series of Prisoner's Wives launched with 4.02 million (17.8%) at 9pm.
On BBC Two, the biggest show of the evening was the 7.30pm episode of Great British Menu, which pulled in 1.95 million (9.11%). Later, Horizon intrigued 1.17 million (5.6%) at 9pm.
ITV's Europa League coverage of Chelsea's tie with Steaua Bucharest collected 3.48 million (15.4%) from 7.45pm.
Channel 4 entertained 1.28 million (5.7%) at 9pm with Born To Be Different, while Gogglebox had 0.81 million (4.1%) at 10pm.
Killers Behind Bars brought 933k (4.1%) to Channel 5 at 9pm, while The Bind and Torture Killer - Born To Kill? followed at 10pm with 733k (4.3%).
Celebrity Juice continues to amuse plenty on ITV2, pulling in 1.01 million (5.8%) at 10pm. At