Silent Witness easily won the ratings on Tuesday outside soaps, overnight data reveals.
The 18th series of the BBC One crime drama gathered an average audience of 6.66 million (29.5%) at 9pm, up from last year's opener by around 500,000 viewers.
Later, Count Arthur Strong returned with 1.62m (12.7%) at 10.35pm.
On BBC Two, The Great British Garden Revival began with 1.56m (7.3%) at 7pm, followed by Six Puppies & Us with 2.75m (12.6%) at 8pm and Billionaires' Paradise: Inside Necker Island with 2.79m (12.4%) at 9pm.
ITV's River Monsters returned with 1.92m (8.9%) at 7.30pm, while Britain's Best Back Gardens interested 2.35m (10.8%) at 8pm. Julia Bradbury's The Wonder of Britain was seen by 1.51m (6.7%) at 9pm (191k/1.2% on +1).
On Channel 4, Dr Christian Jessen's Weighing Up the Enemy brought in 1.00m (4.6%) at 8pm (150k/0.7%), followed by the return of 24 Hours in Police Custody with 1.21m (5.4%) at 9pm (300k/1.9%). Gordon Ramsay's Hotel Hell appealed to 944k (5.9%) at 10pm (145k/1.7%).
Channel 5's Scariest Weather attracted 908k (4.2%) at 8pm, followed by Worst Weather Ever? with 754k (3.3%) at 9pm.
On E4, The 100 continued with 916k (4.1%) at 9pm (160k/1.0%), while the new series of Supernatural began with 428k (2.7%) at 10pm.
ITV2's new series Blue Go Mad in Ibiza entertained 303k (1.3%) at 9pm (105k/0.7%).